Siegler, Robert S. (rss2169)

Robert Stuart Siegler

Jacob H. Schiff Foundations Professor of Psychology and Education

Office Location:

465 GDodge

Scholarly Interests

Dr. Robert Siegler has written 13 books, edited 6 others, and authored more than 250 articles, monographs, and book chapters. His research focuses on how children learn mathematics and how theoretical understanding of mathematical development can be applied to improving that learning. His research led to the prediction, confirmed by subsequent research, that playing certain numerical board games yields broad, rapid, and enduring gains in preschoolers' and elementary school children's numerical understanding, particularly for children from low-income backgrounds.

Dr. Siegler's contributions have been honored in many ways, including being awarded the American Psychological Association's Distinguished Contribution Award in 2005, serving on the U.S. National Mathematics Advisory Panel from 2006-2008, election to the National Academy of Education in 2010, heading the development of a Practice Guide on fractions learning for the U. S. Department of Education in 2010, being appointed Director of the Siegler Center for Innovative Learning at Beijing Normal University in 2012, election to the Society of Experimental Psychologists in 2015, Hommage for Dr. Robert Siegler at Aix en Provence in France 2016, chosen in 2017 for the “in honor of” group of the Federation of Associations in Behavioral and Brain Sciences, and recipient of the 2022 G. Stanley Hall Award for Distinguished Contribution to Developmental Psychology from Division 7 of APA. 


Educational Background

How I Got Into Psychology:

For more information, please see Dr. Siegler’s CV.


Selected Publications

In Press

Barbot, B., Hein, S., Trentacosta, C., Beckmann, J., Bick, J., Crocetti, E., Liu, Y., Fernandez S., Liew, J.,
 Overbeek, G., Ponguta, L., Scheithauer, H., Super, C., Arnett, J., Cook, T., Cooper, C., Côté, J., Eccles,
 J., Eid, M., Hiraki, K., Johnson, M., Juang, L., Landi, N., Leckman, J., Mulvey, L., McCardle, P.,
 Preiss, D., Piquero, A., Siegler, R. S., Soenens, B., Yousafzai, A., Bornstein, M., Goossens, L.,
 Harkness, S., van IJzendoorn, M. (In press). Manifesto for new directions in developmental science.
 New Directions for Child and Adolescent Development.

McMullen, J., & Siegler, R. S. (In press). Spontaneous focusing on multiplicative relations and fraction magnitude knowledge. Mathematical Thinking and Learning.

Siegler, R. S. (In press). Development of numerical knowledge. In O. Houdé & G. Borst (Eds.), The Cambridge handbook of cognitive development. Cambridge, United Kingdom: Cambridge University Press.

Siegler, R. S., Im, S,. Schiller, L., Tian, J., Braithwaite, D. W. (In press). The sleep of reason produces monsters: how and when biased input shapes mathematics learning. Annual Review of Developmental Psychology.

Siegler, R. S., Im, S., Braithwaite, D. W. (In press).Understanding Development Requires Assessing the Environment in Which Learning Occurs: Examples from Mathematics Learning. New Directions for Child and Adolescent Development

Hopkins, S., Russo, J., & Siegler, R. S. (In press). Is counting hindering learning? An investigation into children’s proficiency with simple addition and their flexibility with mental computation strategies. Mathematical Thinking and Learning.


Braithwaite, D. W., & Siegler, R. S. (2020). Putting fractions together. Journal of Educational Psychology. doi: 10.1037/edu0000477

Cui, J., Li, L., Li, M., Siegler, R. S., & Zhou, X. (2020). Middle temporal cortex is involved in processing fractions. Neuroscience Letters, 725, 134901. doi: 10.1016/j.neulet.2020.134901

Mcmullen, J., Hannula-Sormunen, M. M., Lehtinen, E., & Siegler, R. S. (2020). Distinguishing adaptive from routine expertise with rational number arithmetic. Learning and Instruction, 68, 101347. doi: 10.1016/j.learninstruc.2020.101347

Tian, J., Braithwaite, D. W., & Siegler, R. S. (2020). Distributions of textbook problems predict student learning: Data from decimal arithmetic. Journal of Educational Psychology. doi:10.1037/edu0000618

Tian, J., Braithwaite, D. W., & Siegler, R. S. (2020). How do people choose among rational number notations? Cognitive Psychology, 123, 101333. doi:10.1016/j.cogpsych.2020.101333


Braithwaite, D. W., Lieb, E., Siegler, R. S., & McMullen, J. (2019). Individual differences in fraction arithmetic learning. Cognitive Psychology. doi:


Braithwaite, D. W., & Siegler, R. S. Do children understand fraction addition? Developmental Science. Early bird on line publication, September 12, 2017. doi: 10.1111/desc.12601.

Braithwaite, D. W., & Siegler, R. S. Children learn spurious associations in their math textbooks: Examples from fraction arithmetic. Journal of Experimental Psychology: Learning, Memory, and Cognition. doi: 10.1037/xlm0000546

Braithwaite, D. W., & Siegler, R. S. (2018). Developmental changes in whole number bias. Developmental Science, 21(2), e12541. doi: 10.1111/desc.12541.

Tian, J., & Siegler, R. S. (2018). Which type of rational numbers should students learn first? Educational
Psychology Review, 30, 351-372. doi: 10.1007/s10648-017-9417-3


Braithwaite, D. W., Pyke, A. A., & Siegler, R. S.( 2017). A computational model of fraction arithmetic. Psychological Review, 124(5), 603-625. doi: 10.1037/rev0000072

Lortie-Forgues, H., & Siegler, R. S. (2017). Conceptual knowledge of decimal arithmetic. Journal of Educational Psychology, 109(3), 374-386. doi: 10.1037/edu0000148

Siegler, R. S., & Braithwaite, D. W. (2017). Numerical development. Annual Review of Psychology, 68, 187-213. doi: 10.1146/annurev-psych-010416-044101
This article can be accessed here:

Siegler, R. S., & Lortie-Forgues, H. (2017).  Hard lessons: Why rational number arithmetic is so difficult for so many people. Current Directions in Psychological Science, 26(4), 346-351. doi: 10.1177/0963721417700129. NOTE: This article can be accessed at the journal’s website online at:

Tian, J., & Siegler, R. S. (2017). Fractions learning in children with mathematics difficulties. Journal of Learning Disabilities, 50(6), 614-620. doi: 10.1177/0022219416662032

Tian, J., & Siegler, R. S(2017). Which type of rational numbers should students learn first? Educational Psychology Review. Published online publication, July 4, 2017. doi: 10.1007/s10648-017-9417-3.


Fazio, L. K., DeWolf, M., & Siegler, R. S. (2016). Strategy use and strategy choice in fraction magnitude compartison. Journal of Experimental Psychology: Learning, Memory, and Cognition, 42, 1-16 doi: 10.1037/xlm0000153

Fazio, L. K., Kennedy, C., & Siegler, R. S. (2016). Improving children’s knowledge of fraction magnitudes. PLOS ONE. doi: 10.1371/journal/one.0165243

Siegler, R. S. (2016). Continuity and change in the field of cognitive development and in the perspectives of one cognitive developmentalist. Child Development Perspectives, 10(2), 128-133. doi: 10.1111/cdep.12173

Siegler, R. S. (2016). How does change occur? In R. Sternberg, S. Fiske, & D. Foss, (Eds.), Scientists making a difference: One hundred eminent behavioral and brain scientists talk about their most important contributions (pp. 223-227). New York: Cambridge University Press.

Siegler, R. S. (2016). Magnitude knowledge: The common core of numerical development. Developmental Science, 19, 341-361. doi: 10.1111/desc.12395


Bailey, D. H., Zhou, X., Zhang, Y., Cui, J., Fuchs, L. S., Jordan, N. C., Gersten, R., & Siegler, R. S. (2015). Development of fraction concepts and procedures in U.S. and Chinese children. Journal of Experimental Child Psychology, 129, 68-83, early bird on-line publication, September 29, 2014, doi: 10.1016/j.jecp.2014.08.006.

Lortie-Forgues, H., Tian, J., & Siegler, R. S. (2015). Why is learning fraction and decimal arithmetic so difficult? Developmental Review, 38, 201-221, doi: 10.1016/j.dr.2015.07.008

Siegler, R., Fuchs, L., Jordan, N., Gersten, R., & Ochsendorf, R. (2015). The Center for Improving Learning of Fractions: A progress report. In S. Chinn (Ed.), The Routledge international handbook of dyscalculia and mathematical learning difficulties, (pp. 292-303). New York: Routledge.

Siegler, R. S., & Lortie-Forgues, H. (2015). Conceptual knowledge of fraction arithmetic. Journal of Educational Psychology, 107, 909-918. doi: 10.1037/edu0000025

Torbeyns, J., Schneider, M., Xin, Z., & Siegler, R. S. (2015).  Bridging the gap: Fraction understanding is central to mathematics achievement in students from three different continents. Learning and Instruction, 37, 5-13. doi: 2014.03.002.


Bailey, D., Siegler, R. S., & Geary, D. C. (2014).  Early predictors of middle school fraction knowledge. Developmental Science, 17, 775-785, doi: 10.1111/desc.12155.

Fazio, L. K., Bailey, D. H., Thompson, C. A., & Siegler, R. S. (2014). Relations of different types of numerical magnitude representations to each other and to mathematics achievement. Journal of Experimental Child Psychology, 123, 53-72, doi:

Laski, E. V., & Siegler, R. S. (2014). Learning from number board games: You learn what you encode. Developmental Psychology, 50, 853-864, doi: 10.1037/a0034321.

Ramani, G. B., & Siegler, R. S. (2014). How informal learning activities can promote children’s numerical knowledge. In R. C. Kadosh & A. Dowker (Eds.), Oxford handbook of mathematical cognition, published on-line, 3-2014, doi: 10.1093/oxfordhb/9780199642342.013.012.

Siegler, R. S., & Lortie-Forgues, H. (2014). An integrative theory of numerical development. Child Development Perspectives, 8, 144-150, doi: 10.1111/cdep.12077.

Siegler, R. S., & Thompson, C. A. (2014). Numerical landmarks are useful – Except when they’re not. Journal of Experimental Child Psychology, 120, 39-58, doi:

Vukovic, R. K., Fuchs, L. S., Geary, D. C., Jordan, N. C., Gersten, R., & Siegler, R. S. (2014). Sources of individual differences in children’s understanding of fractions. Child Development, 85, 1461-1476, doi: 10.1111/cdev.12218.

Watts, T. W., Duncan, G. J., Siegler, R. S., & Davis-Kean, P. E. (2014).  What’s past is prologue: Relations between early mathematics knowledge and high school achievement. Educational Researcher, 43, 352-360, doi: 10.3102/0013189X14553660.

For other articles Dr. Siegler has written, please download his CV from the Documents Link next to the Wordle above, or see his Selected Publications links at Thank you.

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