@article{wright_delgado_mendoza_2024, title={Exploring the impact of an intervention on pre-service science teachers' attitudes and beliefs about gender and sexual diversity-inclusive science teaching}, volume={4}, ISSN={["1098-2736"]}, DOI={10.1002/tea.21942}, abstractNote={Abstract Exploring how science teacher education programs can prepare science teachers to support gender and sexually diverse students remains an important area for research. A 5‐week intervention was designed for pre‐service science teachers' (PSSTs), addressing gender and sexual diversity (GSD). The effects of the intervention on PSSTs' attitudes and beliefs about GSD‐inclusive science teaching (GSDST) were explored using a multiple case study research design. In addition, the design elements of the intervention that were perceived as most significant were identified. Our results showed that the PSSTs were mostly supportive of measures indicative of GSDST prior to the intervention, and there was an overall trend in favor of GSDST with small effect sizes after the intervention, which did not reach statistical significance. Using thematic analysis, three themes were identified to characterize how their attitudes and beliefs changed throughout the intervention: GSDST is perceived as important for student safety; an “add LGBT and stir” approach to GSDST; and uncertainty of GSD language. Five design features of the intervention that were perceived as most impactful were group dialog; coherence to Ambitious Science Teaching; GSD terminology; knowledge of intersex, hormones, and lesbian, gay, bisexual, transgender, and queer scientists; and relevant case studies. The findings contribute to understanding how science teacher education programs can impact PSSTs' attitudes, beliefs, and intended enactment of GSDST consistent, with recent calls for GSD equity in science education.}, journal={JOURNAL OF RESEARCH IN SCIENCE TEACHING}, author={Wright, Gary William and Delgado, Cesar and Mendoza, K. Rende}, year={2024}, month={Apr} }
 @article{diaz_delgado_han_lynch_2024, title={Using communities of practice to investigate work-integrated learning in engineering education: a grounded theory approach}, volume={5}, ISSN={["1573-174X"]}, url={http://dx.doi.org/10.1007/s10734-024-01225-x}, DOI={10.1007/s10734-024-01225-x}, journal={HIGHER EDUCATION}, author={Diaz, Brayan and Delgado, Cesar and Han, Kevin and Lynch, Collin}, year={2024}, month={May} }
 @article{wright_delgado_2023, title={Generating a framework for gender and sexual diversity-inclusive STEM education}, volume={2}, ISSN={["1098-237X"]}, DOI={10.1002/sce.21786}, abstractNote={Abstract}, journal={SCIENCE EDUCATION}, author={Wright, Gary William and Delgado, Cesar}, year={2023}, month={Feb} }
 @article{wu_chen_sekelsky_peterson_harper-gampp_delgado_2023, title={Shrink or grow the kids? Scale cognition in an immersive virtual environment for K-12 summer camp}, url={http://dx.doi.org/10.1109/vrw58643.2023.00203}, DOI={10.1109/VRW58643.2023.00203}, abstractNote={Virtual reality (VR) has been widely used for education and affords embodied learning experiences. Here we describe: Scale Worlds (SW), an immersive virtual environment to allow users to shrink or grow by powers of ten (10X) and experience entities from molecular to astronomical levels; and students' impressions and outcomes from experiencing SW in a CAVE (Figure 1) during experiential summer outreach sessions. Data collected from post-visit surveys of 69 students, and field observations, revealed that VR technologies: enabled interactive learning experiences; encouraged active engagement and discussions among participating students; enhanced the understanding of size and scale; and increased interest in STEM careers.}, journal={2023 IEEE CONFERENCE ON VIRTUAL REALITY AND 3D USER INTERFACES ABSTRACTS AND WORKSHOPS, VRW}, publisher={IEEE}, author={Wu, Linfeng and Chen, Karen B. and Sekelsky, Brian and Peterson, Matthew and Harper-Gampp, Tyler and Delgado, Cesar}, year={2023}, pages={721–722} }
 @article{you_park_marshall_delgado_2022, title={Interdisciplinary Science Assessment of Carbon Cycling: Construct Validity Evidence Based on Internal Structure}, volume={52}, ISSN={["1573-1898"]}, DOI={10.1007/s11165-020-09943-9}, number={2}, journal={RESEARCH IN SCIENCE EDUCATION}, author={You, Hye Sun and Park, Sunyoung and Marshall, Jill A. and Delgado, Cesar}, year={2022}, month={Apr}, pages={473–492} }
 @article{jones_nieuwsma_rende_carrier_refvem_delgado_grifenhagen_huff_2022, title={Leveraging the epistemic emotion of awe as a pedagogical tool to teach science}, volume={10}, ISSN={["1464-5289"]}, url={https://doi.org/10.1080/09500693.2022.2133557}, DOI={10.1080/09500693.2022.2133557}, abstractNote={ABSTRACT Awe is a complex emotion theorised to impact science learning and practice. In science education, awe has the potential to motivate explanation-seeking, promote conceptual change, and instill feelings of connectedness to the natural world. This exploratory study examined teachers’ experiences with awe as well as their uses of awe in their science instruction. Thirty-four elementary (grades 4-5; n =14) and middle school (grades 6-7; n = 20) teachers completed a survey of awe perceptions and experiences and participated in a semi-structured interview. Results showed that science teachers report using awe-invoking classroom experiences in a variety of science disciplines with the intention of leveraging the emotional response in ways that facilitate learning outcomes and inspire long-term science interest. Teachers also reported numerous dispositional factors they perceived as being influential in governing awe experiences in science instruction including age, prior experiences, interest, curiosity, and the presence of co-occurring emotions. This study adds to the developing body of work around awe and science instruction, supports the findings from other fields related to the epistemic and self-transcendent nature of awe, and suggests that awe can be used to enhance science teaching and learning.}, journal={INTERNATIONAL JOURNAL OF SCIENCE EDUCATION}, author={Jones, M. Gail and Nieuwsma, Julianna and Rende, K. and Carrier, Sarah and Refvem, Emma and Delgado, Cesar and Grifenhagen, Jill and Huff, Pamela}, year={2022}, month={Oct} }
 @article{you_park_delgado_2021, title={A closer look at US schools: What characteristics are associated with scientific literacy? A multivariate multilevel analysis using PISA 2015}, volume={105}, ISSN={["1098-237X"]}, DOI={10.1002/sce.21609}, abstractNote={Abstract}, number={2}, journal={SCIENCE EDUCATION}, author={You, Hye Sun and Park, Sunyoung and Delgado, Cesar}, year={2021}, month={Mar}, pages={406–437} }
 @article{peterson_delgado_tang_bordas_norville_2021, title={A taxonomy of cognitive image functions for science curriculum materials: identifying and creating 'performative' visual displays}, volume={43}, ISSN={["1464-5289"]}, DOI={10.1080/09500693.2020.1868609}, abstractNote={ABSTRACT Pedagogical content knowledge of science teachers includes knowledge of representational forms, such as visual displays. Past research has provided a general means to evaluate pictures, but is not fine-grained on features internal to pictures. Furthermore, many existing picture function typologies consider pictures as subservient to text, though pictures have their own explanatory power. We here adapt a general ‘performative’ image function typology into a science-specific taxonomy of cognitive image functions with fine-grained distinctions of design strategies related to interpretative processes. The authors, including science educators and graphic designers, refined and expanded functions of imagery using visual displays in science textbooks following a constant comparison method. The resulting performative image function taxonomy consists of a structural framework that distinguishes conceptual elements internal to pictures (i.e. concepts, entities, components, attributes, adjuncts, configurations); a process model that identifies three interpretative phases necessary to understand visual displays (i.e. approach, activity, outcome); and 17 functions across the interpretative phases. We demonstrate these functions through analysis of and modifications to visual displays from science textbooks. Many of the modifications presented here can be repeated with rudimentary drawing over existing illustrations (e.g. arrows, dividing lines, labels), and they are thus accessible to science teachers and students.}, number={2}, journal={INTERNATIONAL JOURNAL OF SCIENCE EDUCATION}, author={Peterson, Matthew and Delgado, Cesar and Tang, Kok-Sing and Bordas, Clement and Norville, Kayla}, year={2021}, month={Jan}, pages={314–343} }
 @article{green_delgado_2021, title={Crossing cultural borders: results of an intervention on community college biology students' understanding and acceptance of evolution}, volume={43}, ISSN={["1464-5289"]}, DOI={10.1080/09500693.2020.1869854}, abstractNote={ABSTRACT Evolution is an essential underlying concept in biology. Previous research demonstrates that many obstacles exist that prevent successful teaching and learning about evolution. This research study used the theoretical framework of cultural border crossing and its underlying cognitive explanation, collateral learning, to design an intervention for community college students in an introductory biology class for non-science majors. Cultural border crossing explains that learners might encounter extensive differences between their home cultures and the culture of the science classroom and may need assistance in navigating the crossing of these cultural borders. Collateral learning is the cognitive mechanism that can be used to resolve potentially conflicting schemata within one’s cognitive structure. Quantitative data show a small positive effect on the students’ understanding and acceptance. Qualitative data show how students’ understanding and acceptance of evolution change after the intervention and when cultural border crossing and collateral learning occur. Results and themes suggest that more research is needed on how students’ cultures influence their learning about evolution and how educators can best facilitate learning among students with various cultural beliefs about the diversity of life on Earth.}, number={4}, journal={INTERNATIONAL JOURNAL OF SCIENCE EDUCATION}, author={Green, Kathryn and Delgado, Cesar}, year={2021}, month={Mar}, pages={469–496} }
 @article{smith_delgado_2021, title={Developing a Model of Graduate Teaching Assistant Teacher Efficacy: How Do High and Low Teacher Efficacy Teaching Assistants Compare?}, volume={20}, ISSN={["1931-7913"]}, DOI={10.1187/cbe.20-05-0096}, abstractNote={ This study identifies factors that influence the development of teacher efficacy in STEM graduate teaching assistants over the course of one semester. Those with high teacher efficacy draw upon mastery experience, vicarious experience, and verbal and social persuasions from reliable sources, such as professors and accomplished peers. }, number={1}, journal={CBE-LIFE SCIENCES EDUCATION}, author={Smith, Cody R. and Delgado, Cesar}, year={2021}, month={Mar} }
 @inbook{delgado_jones_parker_2021, place={Arlington, VA}, title={Scale, proportion, and quantity}, booktitle={Crosscutting Concepts: Strengthening Science and Engineering Learning}, publisher={NSTA Press}, author={Delgado, C. and Jones, M.G. and Parker, D.}, editor={Nordine, J. and Lee, O.Editors}, year={2021} }
 @article{jin_delgado_bauer_wylie_cisterna_llort_2019, title={A hypothetical learning progression for quantifying phenomena in science}, volume={28}, ISSN={["1573-1901"]}, DOI={10.1007/s11191-019-00076-8}, number={9-10}, journal={Science & Education}, publisher={Science & Education}, author={JIn, H. and Delgado, C. and Bauer, M. and Wylie, E.C. and Cisterna, D. and Llort, K.}, year={2019}, month={Dec}, pages={1181–1208} }
 @article{lucero_delgado_green_2019, title={Elucidating High School Biology Teachers’ Knowledge of Students’ Conceptions Regarding Natural Selection}, volume={8}, ISSN={1571-0068 1573-1774}, url={http://dx.doi.org/10.1007/s10763-019-10008-1}, DOI={10.1007/s10763-019-10008-1}, journal={International Journal of Science and Mathematics Education}, publisher={Springer Science and Business Media LLC}, author={Lucero, Margaret M. and Delgado, Cesar and Green, Kathryn}, year={2019}, month={Aug} }
 @inproceedings{yoon_delgado_mckenna_krajcik_levites_sussman_2019, place={Charlottesville, VA}, title={The integration of cross-cutting concepts in three-dimensional learning}, url={http://curry.virginia.edu/CCC-Summit.}, booktitle={Summit for examining the potential for crosscutting concepts to support three-dimensional learning conference proceedings}, publisher={University of Virginia}, author={Yoon, S. and Delgado, C. and McKenna, T.J. and Krajcik, J.S. and Levites, L. and Sussman, A.}, editor={Fick, S.J. and Nordine, J. and McElhaney, K.W.Editors}, year={2019} }
 @article{you_marshall_delgado_2019, title={Toward Interdisciplinary Learning: Development and Validation of an Assessment for Interdisciplinary Understanding of Global Carbon Cycling}, volume={51}, ISSN={0157-244X 1573-1898}, url={http://dx.doi.org/10.1007/s11165-019-9836-x}, DOI={10.1007/s11165-019-9836-x}, number={5}, journal={Research in Science Education}, publisher={Springer Science and Business Media LLC}, author={You, Hye Sun and Marshall, Jill A. and Delgado, Cesar}, year={2019}, month={Mar}, pages={1197–1221} }
 @inproceedings{delgado_peterson_2018, place={London, UK}, title={An enhanced framework for scale cognition leveraging visual metaphor theory and analogical reasoning theory}, volume={3}, url={http://ccl.northwestern.edu/2018/ICLS2018Volume3_proceedings.pdf}, booktitle={Rethinking learning in the digital age: Making the learning sciences count. 13th International Conference of the Learning Sciences (ICLS) 2018}, publisher={International Society of the Learning Sciences}, author={Delgado, C. and Peterson, M.}, editor={Kay, J. and Luckin, R.Editors}, year={2018}, pages={1607–1608} }
 @article{green_langerhans_dempsey_delgado_2018, title={The Evolution of a Partnership}, volume={041}, ISSN={0887-2376}, url={http://dx.doi.org/10.2505/4/ss18_041_08_41}, DOI={10.2505/4/ss18_041_08_41}, number={08}, journal={Science Scope}, publisher={National Science Teachers Association (NSTA)}, author={Green, Kathryn and Langerhans, Brian and Dempsey, Melissa and Delgado, Cesar}, year={2018} }
 @article{you_marshall_delgado_2017, title={Assessing students' disciplinary and interdisciplinary understanding of global carbon cycling}, volume={55}, ISSN={0022-4308}, url={http://dx.doi.org/10.1002/tea.21423}, DOI={10.1002/tea.21423}, abstractNote={Abstract}, number={3}, journal={Journal of Research in Science Teaching}, publisher={Wiley}, author={You, Hye Sun and Marshall, Jill A. and Delgado, Cesar}, year={2017}, month={Oct}, pages={377–398} }
 @article{delgado_jones_you_robertson_chesnutt_halberda_2017, title={Scale and the evolutionarily based approximate number system: an exploratory study}, volume={39}, ISSN={["1464-5289"]}, DOI={10.1080/09500693.2017.1312626}, abstractNote={ABSTRACT Crosscutting concepts such as scale, proportion, and quantity are recognised by U.S. science standards as a potential vehicle for students to integrate their scientific and mathematical knowledge; yet, U.S. students and adults trail their international peers in scale and measurement estimation. Culturally based knowledge of scale such as measurement units may be built on evolutionarily-based systems of number such as the approximate number system (ANS), which processes approximate representations of numerical magnitude. ANS is related to mathematical achievement in pre-school and early elementary students, but there is little research on ANS among older students or in science-related areas such as scale. Here, we investigate the relationship between ANS precision in public school U.S. seventh graders and their accuracy estimating the length of standard units of measurement in SI and U.S. customary units. We also explored the relationship between ANS and science and mathematics achievement. Accuracy estimating the metre was positively and significantly related to ANS precision. Mathematics achievement, science achievement, and accuracy estimating other units were not significantly related to ANS. We thus suggest that ANS precision may be related to mathematics understanding beyond arithmetic, beyond the early school years, and to the crosscutting concepts of scale, proportion, and quantity.}, number={8}, journal={INTERNATIONAL JOURNAL OF SCIENCE EDUCATION}, author={Delgado, Cesar and Jones, M. Gail and You, Hye Sun and Robertson, Laura and Chesnutt, Katherine and Halberda, Justin}, year={2017}, pages={1008–1024} }
 @article{lucero_petrosino_delgado_2016, title={Exploring the relationship between secondary science teachers’ subject matter knowledge and knowledge of student conceptions while teaching evolution by natural selection}, volume={54}, ISSN={0022-4308}, url={http://dx.doi.org/10.1002/tea.21344}, DOI={10.1002/tea.21344}, abstractNote={The fundamental scientific concept of evolution occurring by natural selection is home to many deeply held alternative conceptions and considered difficult to teach. Science teachers’ subject matter knowledge (SMK) and the pedagogical content knowledge (PCK) component of knowledge of students’ conceptions (KOSC) can be valuable resources for helping students learn difficult science concepts such as natural selection. However, little research exists that explores the relationship between science teachers’ SMK and their KOSC on evolution by natural selection. This study explores the relationship between SMK and KOSC through the participation of four biology teachers at a single high school and thus deepens our understanding of the teacher knowledge base. Main data sources are teacher interviews in which each teacher answered SMK-type questions and predicted what their students’ most common alternative conceptions were by using the Conceptual Inventory of Natural Selection (CINS). Other data sources include student responses on the CINS and classroom observations. Findings revealed relative independence between SMK and KOSC, although there is likely a minimum threshold of SMK to recognize student alternative conceptions. However, our work also revealed ways in which teachers were not leveraging their KOSC and suggest potential avenues for future inquiry. © 2016 Wiley Periodicals, Inc. J Res Sci Teach 54: 219–246, 2017}, number={2}, journal={Journal of Research in Science Teaching}, publisher={Wiley}, author={Lucero, Margaret M. and Petrosino, Anthony J. and Delgado, Cesar}, year={2016}, month={Aug}, pages={219–246} }
 @article{delgado_stevens_shin_krajcik_2015, title={A middle school instructional unit for size and scale contextualized in nanotechnology}, volume={4}, ISSN={2191-9097 2191-9089}, url={http://dx.doi.org/10.1515/ntrev-2014-0023}, DOI={10.1515/ntrev-2014-0023}, abstractNote={Abstract}, number={1}, journal={Nanotechnology Reviews}, publisher={Walter de Gruyter GmbH}, author={Delgado, Cesar and Stevens, Shawn Y. and Shin, Namsoo and Krajcik, Joseph}, year={2015}, month={Jan} }
 @article{delgado_lucero_2015, title={Scale construction for graphing: An investigation of students' resources}, volume={52}, ISSN={0022-4308}, url={http://dx.doi.org/10.1002/tea.21205}, DOI={10.1002/tea.21205}, abstractNote={Graphing is a fundamental part of the scientific process. Scales are key but little-studied components of graphs. Adopting a resources-based framework of cognitive structure, we identify the potential intuitive resources that six undergraduates of diverse majors and years at a public US research university activated when constructing scales, and identify classes of resources that share similar characteristics. The students constructed scales for data sets that range over 10 or more orders of magnitude, and were interviewed in depth about their scales. The data were analyzed using the constant comparative method. We identified four classes of resources: (1) “prior drawing experience” resources that include show all elements and what you see is what you get; (2) “wide range” resources that are used to make sense of a data set with widely varying values, such as zoom in, ratio, and conversion; (3) “prior graphing experience” resources that draw from previous work with graphing, including powers-of-ten scales and linear scales; and (4) “fundamental knowledge” resources, such as halving. These resources, while identified among undergraduates, may indicate promising educational approaches to graphing in middle and high school. Secondary school science curricula and instruction that acknowledge and build on student resources will likely result in deeper understanding of conventional scales and graphs among students at this age and thus allow for more effective instruction at the undergraduate level. Instructional activities that might activate and build upon the resources identified are presented. © 2015 Wiley Periodicals, Inc. J Res Sci Teach 52: 633–658, 2015.}, number={5}, journal={Journal of Research in Science Teaching}, publisher={Wiley}, author={Delgado, Cesar and Lucero, Margaret M.}, year={2015}, month={Feb}, pages={633–658} }
 @article{tang_delgado_moje_2014, title={An Integrative Framework for the Analysis of Multiple and Multimodal Representations for Meaning-Making in Science Education}, volume={98}, ISSN={0036-8326}, url={http://dx.doi.org/10.1002/sce.21099}, DOI={10.1002/sce.21099}, abstractNote={ABSTRACT}, number={2}, journal={Science Education}, publisher={Wiley}, author={Tang, Kok Sing and Delgado, Cesar and Moje, Elizabeth Birr}, year={2014}, month={Jan}, pages={305–326} }
 @article{delgado_2014, title={Collective landmarks for deep time: a new tool for evolution education}, volume={48}, ISSN={0021-9266 2157-6009}, url={http://dx.doi.org/10.1080/00219266.2013.849280}, DOI={10.1080/00219266.2013.849280}, abstractNote={Evolution is a fundamental, organising concept in biology, yet there is widespread resistance to evolution among US students and there are rising creationist challenges in Europe. Resistance to evolution is linked to lack of understanding of the age of the Earth. An understanding of deep time is thus essential for effective biology education. Landmarks – well-known events of known absolute age – are important in developing a mental framework for deep time. ‘Collective landmarks’ are important events of which a group of students has accurate and precise knowledge. The collective landmarks for time were determined in several semesters of an interdisciplinary undergraduate course at a US public research university. A written survey was employed that asked students to select the appropriate ten-fold time range for ten important cosmological, biological and historical events. The collective landmarks were very similar across classes, including the Big Bang and the Cold War, and there was progress developing additional landmarks. No statistically significant differences in accuracy of estimation were detected across science, technology, engineering and mathematics (STEM) and social sciences majors. The potential utility of collective landmarks within a single biology course, and across a university biology programme, is described.}, number={3}, journal={Journal of Biological Education}, publisher={Informa UK Limited}, author={Delgado, Cesar}, year={2014}, month={Jan}, pages={133–141} }
 @article{delgado_2014, title={Navigating Tensions Between Conceptual and Metaconceptual Goals in the Use of Models}, volume={24}, ISSN={1059-0145 1573-1839}, url={http://dx.doi.org/10.1007/s10956-014-9495-7}, DOI={10.1007/s10956-014-9495-7}, number={2-3}, journal={Journal of Science Education and Technology}, publisher={Springer Science and Business Media LLC}, author={Delgado, Cesar}, year={2014}, month={Jun}, pages={132–147} }
 @inproceedings{delgado_lucero_2014, place={Boulder, CO}, title={Students’ resources for the construction of scales for graphing}, volume={1}, url={https://repository.isls.org//handle/1/1122}, booktitle={Learning and Becoming in Practice: The International Conference of the Learning Sciences (ICLS) 2014}, publisher={International Society of the Learning Sciences}, author={Delgado, Cesar and Lucero, Margaret}, editor={Polman, Joseph L. and Kyza, Eleni A. and O'Neill, Kevin and Tabak, Iris and Penuel, William R. and Jurow, A. Susan and O'Connor, Kevin and Lee, Tiffany and D'Amico, LauraEditors}, year={2014}, pages={262–269} }
 @article{sun you_delgado_2014, title={Toward an Interdisciplinary Science Curriculum: Analysis of the Connections across Science Learning Progressions}, volume={4}, ISSN={2042-6364}, url={http://dx.doi.org/10.20533/ijcdse.2042.6364.2014.0258}, DOI={10.20533/ijcdse.2042.6364.2014.0258}, abstractNote={Learning progression (LP) studies potentially bring vertical coherence to individual big ideas in science education. However, since natural phenomena are associated with big ideas in a variety of science disciplines, the interdisciplinary connections across big ideas should be considered in science education. This study addresses an important question to developing an exemplary interdisciplinary curriculum: how do existing LPs relate to one another across disciplinary boundaries? This research analyzed 17 published LPs for 10 big ideas: matter, genetics, energy, carbon cycling, force and motion, celestial motion, biodiversity, evolution, ecological systems, and water. A content analysis was conducted to establish how these big ideas formed interdisciplinary relationships. A three-dimensional representation of the LPs including their levels and the interconnections among levels was developed. The approach modeled in this study can inform the development of standards and materials for an interdisciplinary science curriculum.}, number={Special 1}, journal={International Journal for Cross-Disciplinary Subjects in Education}, publisher={Infonomics Society}, author={Sun You, Hye and Delgado, Cesar}, year={2014}, month={Mar}, pages={1854–1862} }
 @inproceedings{you_delgado_2014, place={Basildon, UK}, title={Weaving an interdisciplinary science curriculum: Analysis of the connections across learning progressions}, booktitle={Canada International Conference on Education Conference Proceedings}, publisher={CICE}, author={You, Hye Sun and Delgado, Cesar}, editor={Shoniregun, C.A. and Akmayeva, G.A.Editors}, year={2014}, pages={68–71} }
 @article{delgado_2013, title={Cross-cultural Study of Understanding of Scale and Measurement: Does the everyday use of US customary units disadvantage US students?}, volume={35}, ISSN={0950-0693 1464-5289}, url={http://dx.doi.org/10.1080/09500693.2013.779761}, DOI={10.1080/09500693.2013.779761}, abstractNote={Following a sociocultural perspective, this study investigates how students who have grown up using the SI (Système International d'Unités) (metric) or US customary (USC) systems of units for everyday use differ in their knowledge of scale and measurement. Student groups were similar in terms of socioeconomic status, curriculum, native language transparency of number word structure, type of school, and makeup by gender and grade level, while varying by native system of measurement. Their performance on several tasks was compared using binary logistic regression, ordinal logistic regression, and analysis of variance, with gender and grade level as covariates. Participants included 17 USC-native and 89 SI-native students in a school in Mexico, and 31 USC-native students in a school in the Midwestern USA. SI-native students performed at a significantly higher level estimating the length of a metre and a conceptual task (coordinating relative size and absolute size). No statistically significant differences were found on tasks involving factual knowledge about objects or units, scale construction, or estimation of other units. USC-native students in the US school performed at a higher level on smallest known object. These findings suggest that the more transparent SI system better supports conceptual thinking about scale and measurement than the idiosyncratic USC system. Greater emphasis on the SI system and more complete adoption of the SI system for everyday life may improve understanding among US students. Advancing sociocultural theory, systems of units were found to mediate learner's understanding of scale and measurement, much as number words mediate counting and problem solving.}, number={8}, journal={International Journal of Science Education}, publisher={Informa UK Limited}, author={Delgado, Cesar}, year={2013}, month={Jun}, pages={1277–1298} }
 @article{delgado_2013, title={Navigating Deep Time: Landmarks for Time From the Big Bang to the Present}, volume={61}, ISSN={1089-9995 2158-1428}, url={http://dx.doi.org/10.5408/12-300.1}, DOI={10.5408/12-300.1}, abstractNote={ABSTRACT People make sense of the world by comparing and relating new information to their existing landmarks. Each individual may have different landmarks, developed through idiosyncratic experiences. Identifying specific events that constitute landmarks for a group of learners may help instructors in gauging students' prior knowledge and in planning instruction that helps students build additional landmarks events. This paper proposes an operationalized definition for collective landmarks based on importance, accuracy, and precision. Including precision in the definition allows landmarks to be characterized for a group rather than an individual. This study evaluated the ability of undergraduate students in an interdisciplinary course to estimate scales of time related to major cosmological, geological, and historical events. Individual students responded to replicate questions in different formats with the same answers, indicating the testing format was valid. The students' estimates were then used to determine collective landmarks. The number of collective landmarks increased between the pretest and posttest. Collective landmarks included extremely ancient events (Big Bang, formation of the solar system) or relatively recent ones (Cold War, the age of empires, emergence of nation states). Intermediate events had low accuracy, low precision, or both. These data indicate that lecture courses can teach students collective landmarks for time. Because landmarks can be learned, geoscience programs might consider coordinated planning of key landmarks to be introduced at different stages of their academic programs.}, number={1}, journal={Journal of Geoscience Education}, publisher={Informa UK Limited}, author={Delgado, Cesar}, year={2013}, month={Feb}, pages={103–112} }
 @inproceedings{delgado_morton_2012, place={Sydney, NSW, Australia}, title={Learning progressions, learning trajectories, and equity}, volume={1}, url={https://repository.isls.org//handle/1/2205}, booktitle={The Future of Learning: Proceedings of the 10th International Conference of the Learning Sciences (ICLS 2012)}, publisher={International Society of the Learning Sciences}, author={Delgado, C. and Morton, K.}, editor={van Aalst, J. and Thompson, K. and Jacobson, M.J. and Reimann, P.Editors}, year={2012}, pages={204–211} }
 @inbook{delgado_2012, title={Spatial thinking and dimensionality}, ISBN={9780813724867}, ISSN={0072-1077}, url={http://dx.doi.org/10.1130/2012.2486(11)}, DOI={10.1130/2012.2486(11)}, abstractNote={The dimensionality of an object is “the number of coordinates needed to specify a point on the object” (Weisstein, 2003, p. 735). A point has zero dimensions. Higher dimensions can be visualized as the product of displacing an object with lower dimensions. For instance, a line can be thought of as the end product of dragging a point, and thus a line is one-dimensional. A line can be displaced to create a (2-D) rectangle, and a rectangle can be dragged to create a (3-D) rectangular prism (Weis stein, 2003). Time can also be treated as a dimension, so processes involving changes over time in 3-D objects can be thought of as four-dimensional. Higher dimensions exist as well, but they are more diffi cult to portray in physical terms. Many geoscience practices involve using, creating, or interpreting 2-D representations of 3-D objects, including the three key competencies required by the geoscientist in Liben and Titus’s vignette. (1) Reading and navigating with maps involves planning and traveling routes through the physical, 3-D world with the use of a 2-D map. (2) Observing and measuring orientations involves recording orientations of sedimentary layers forming the 3-D mesa on the 2-D map. (3) Interpreting spatial diagrams also requires the coordination of two and three dimensions, using 2-D cross sections “to get a sense of the threedimensional structure” (Liben and Titus, this volume). Liben and Titus’s suggestions for teaching the key competencies also focus on the coordination between the two and three dimensionality of phenomena and representations. Three-dimensional maps can scaffold students’ understanding of 2-D maps, and simulations where virtual 3-D landscapes are fl ooded with water can graphically illustrate the meaning of 2-D contour lines. Exercises where students fi nd cues in the environment to locate their position on the map, and then rotate maps in order to align them with the terrain, can build learners’ mapping skills; these exercises again involve coordinating 2and 3-D data. Actual, physical observations and exercises observing the orientations of planar (2-D) surfaces of 3-D phenomena (e.g., water levels) can also help students. Finally, the authors suggest using computer simulations that show multiple 2-D representations of 3-D phenomena, and exercises featuring “physical objects paired with two-dimensional representations to help students see the links between real-world structures and two-dimensional representations” (p. 65). These teaching strategies are required because students “may have had only limited training and experience in using the tools needed to represent space or to mentally manipulate those representations” (p. 52). There is yet another dimension of spatial thinking that poses challenges to students, which geoscience educators need to consider in planning their}, booktitle={Geological Society of America Special Papers}, publisher={Geological Society of America}, author={Delgado, Cesar}, year={2012}, month={Apr}, pages={71–73} }
 @inbook{cahill_delgado_song_2010, place={Arlington, VA}, title={Engaging students in content learning and scientific critique through a nanoscience context}, booktitle={Exemplary science for resolving societal challenges}, publisher={NSTA Press}, author={Cahill, C. and Delgado, C. and Song, M.}, editor={Yager, R.E.Editor}, year={2010} }
 @inbook{delgado_krajcik_2010, title={Technology Supports for Science Learning}, ISBN={9780080448947}, url={http://dx.doi.org/10.1016/B978-0-08-044894-7.00729-6}, DOI={10.1016/B978-0-08-044894-7.00729-6}, abstractNote={Technology, if accompanied by innovative curriculum and professional development, can transform science learning by supporting active, inquiry-oriented teaching that is consistent with constructivism. Technology tools presently being used to support science learning include probes for real-time data acquisition, computer simulations, modeling software and microworlds, virtual communities and collaborative websites, virtual laboratories, remote access to instruments, software to support and structure student investigations, and learning environments that may include many of these tools along with inquiry-oriented curriculum. Technology can also increase equity and access and help address issues of sustainability and scaling up of educational innovations.}, booktitle={International Encyclopedia of Education}, publisher={Elsevier}, author={Delgado, C. and Krajcik, J.}, year={2010}, pages={197–203} }
 @inproceedings{delgado_2010, place={Chicago}, title={Units of length: A notational system for conceptual understanding of size and scale}, volume={2}, booktitle={Learning in the disciplines: Proceedings of the 9th International Conference of the Learning Sciences (ICLS)}, publisher={International Society of the Learning Sciences}, author={Delgado, C.}, editor={Gomez, K. and Lyons, L. and Radinsky, J.Editors}, year={2010}, pages={362–363} }
 @article{stevens_delgado_krajcik_2009, title={Developing a hypothetical multi-dimensional learning progression for the nature of matter}, volume={47}, ISSN={0022-4308 1098-2736}, url={http://dx.doi.org/10.1002/tea.20324}, DOI={10.1002/tea.20324}, abstractNote={Abstract}, number={6}, journal={Journal of Research in Science Teaching}, publisher={Wiley}, author={Stevens, Shawn Y. and Delgado, César and Krajcik, Joseph S.}, year={2009}, month={Aug}, pages={687–715} }
 @article{beyer_delgado_davis_krajcik_2009, title={Investigating teacher learning supports in high school biology curricular programs to inform the design of educative curriculum materials}, volume={46}, ISSN={0022-4308 1098-2736}, url={http://dx.doi.org/10.1002/tea.20293}, DOI={10.1002/tea.20293}, abstractNote={Abstract}, number={9}, journal={Journal of Research in Science Teaching}, publisher={Wiley}, author={Beyer, Carrie J. and Delgado, Cesar and Davis, Elizabeth A. and Krajcik, Joseph}, year={2009}, month={Nov}, pages={977–998} }
 @inproceedings{pellegrino_krajcik_stevens_swarat_shin_delgado_2008, place={Utrecht, the Netherlands}, title={Using Construct-Centered Design to align curriculum, instruction, and assessment development in emerging science}, volume={3}, booktitle={Proceedings from ICLS ’08: International perspectives in the Learning Sciences: Creating a learning world}, publisher={International Society of the Learning Sciences}, author={Pellegrino, J. and Krajcik, J. and Stevens, S. and Swarat, S. and Shin, N. and Delgado, C.}, editor={Kanselaar, G. and Jonker, V. and Kirschner, P.A. and Prins, F.Editors}, year={2008}, pages={314–321} }
 @inproceedings{stevens_delgado_shin_krajcik_2007, title={Developing and validating a learning progression for the nature of matter}, volume={233}, booktitle={Abstracts of Papers of the American Chemical Society}, author={Stevens, S. and Delgado, C. and Shin, N. and Krajcik, J.}, year={2007}, pages={661} }
 @article{stevens_krajcik_delgado_elgammal_quintana_rosenquist_yunker_2007, title={Identification of the big ideas in nanoscience}, volume={233}, journal={Abstracts of Papers of the American Chemical Society}, author={Stevens, S. and Krajcik, J. and Delgado, C. and Elgammal, R. and Quintana, C. and Rosenquist, A. and Yunker, M.}, year={2007}, pages={678} }
 @inproceedings{hutchinson_stevens_shin_delgado_yunker_bodner_giordano_krajcik_2007, title={Secondary students’ interests in nanoscience concepts and phenomena}, volume={233}, booktitle={Abstracts of Papers of the American Chemical Society}, author={Hutchinson, K. and Stevens, S. and Shin, N. and Delgado, C. and Yunker, M. and Bodner, G. and Giordano, N. and Krajcik, J.}, year={2007}, pages={731–761} }
 @inproceedings{delgado_stevens_krajcik_2007, title={Size and scale curricular activities for middle school}, volume={233}, booktitle={Abstracts of Papers of the American Chemical Society}, author={Delgado, C. and Stevens, S. and Krajcik, J.}, year={2007}, pages={674–674} }
 @inproceedings{delgado_stevens_krajcik_2007, title={Students’ conceptions of size}, volume={233}, booktitle={Abstracts of Papers of the American Chemical Society}, author={Delgado, C. and Stevens, S. and Krajcik, J.}, year={2007}, pages={666} }
 @inproceedings{shin_quintana_delgado_stevens_krajcik_2007, title={The nanoworld: Research-driven design process}, volume={233}, booktitle={Abstracts of Papers of the American Chemical Society}, author={Shin, N. and Quintana, C. and Delgado, C. and Stevens, S. and Krajcik, J.}, year={2007}, pages={657–657} }
 @inproceedings{cahill_stevens_shin_delgado_krajcik_yunker_2007, title={Using small-group discussions to assess student learning of nanoscale concepts}, volume={233}, booktitle={Abstracts of Papers of the American Chemical Society}, author={Cahill, C. and Stevens, S. and Shin, N. and Delgado, C. and Krajcik, J. and Yunker, M.}, year={2007}, pages={639–639} }
 @book{beyer_delgado_davis_krajcik_2006, place={Ann Arbor, MI}, title={Investigating high school biology texts as educative curriculum materials: Curriculum review process}, url={http://www.umich.edu/~hiceweb/papers/2006/BeyerEtAl2006.pdf}, institution={University of Michigan}, author={Beyer, C. and Delgado, C. and Davis, E.A. and Krajcik, J.S.}, year={2006} }
 @article{delgado_2002, title={Dinámica de grupos e identificación proyectiva en el contexto escolar (Group dynamics and projective identification in the school context)}, volume={13}, number={66, 67}, journal={Revista Mexicana de Pedagogía}, author={Delgado, C.}, year={2002}, pages={3–9, 19–23} }
 @article{castro_delgado_signoret_2000, title={Los cuentos de hadas en la pedagogía nacional (Fairy tales in Mexican pedagogy)}, volume={11, 12}, number={55, 56, 57}, journal={Revista Mexicana de Pedagogía}, author={Castro, M. and Delgado, C. and Signoret, A.}, year={2000}, pages={26–31, 20–24, 15–21} }
 @article{delgado_1999, title={Cómo fomentar el pensamiento abstracto en clase de matemáticas (Encouraging abstract thought in mathematics class)}, volume={3}, number={34}, journal={Correo del Maestro}, author={Delgado, C.}, year={1999}, pages={5–7} }
 @article{delgado_1999, title={Un ejercicio constructivista en química (A constructivist exercise in chemistry)}, volume={4}, number={40}, journal={Correo del Maestro}, author={Delgado, C.}, year={1999}, pages={5–9} }