#### In press

Johnson, H. L., McClintock, E., Kalir, R., & Olson, G. (in press) Networking theories to design dynamic covariation techtivities for college algebra students. *Proceedin**gs of the 21st Meeting of the MAA Special Interest Group on Research in Undergraduate Mathematics Education*. San Diego, CA: RUME

#### 2017

Johnson, H. L., McClintock, E., Hornbein, P., Gardner, A., & Grieser, D. (2017). When a critical aspect is a conception: Using multiple theories to design dynamic computer environments and tasks to foster students’ discernment of covariation. 10th Congress of European Research in Mathematics Education, Dublin, Ireland

2017_JohnsonEtAl_CERME10Tzur, R., Johnson, H. L., Norton, A., Davis, A., Wang, X., Ferrara, M., Jorgensen, C. & Wei, B. (2017). Conception of number as a composite unit predicts students’ multiplicative reasoning: Quantitative corroboration of Steffe’s model. In B. Kaur, W. K. Ho, T. L. Toh, & B. H. Choy (Eds.), Proceedings of the 41st Conference of the International Group for the Psychology of Mathematics Education (Vol. 4, pp. 289-296). Singapore: PME.

2017_PME-41_TzurEtAl#### 2016

Hodkowski , N. M., Hornbein, P., Gardner, A., Johnson, H. L., Jorgensen, C., & Tzur, R. 2016, November). Designing a stage-sensitive written assessment of elementary students’ scheme for multiplicative reasoning. In M. B. Wood, E. E. Turner, M. Civil, & J. A. Eli (Eds.), Proceedings of the 38th annual meeting of the North American Chapter of the International Group for the Psychology of Mathematics Education (pp. 1581-1587). Tucson, AZ: The University of Arizona.

HodkowskiEtAl_PMENA_2016Johnson, H. L. (2016, July). Designing technology-rich tasks to foster secondary students’ covariational reasoning. 13th International Congress on Mathematical Education, Hamburg, Germany.

TSG36_PA_Johnson#### 2015

Johnson, H. L. (2015, July). Task design: Fostering secondary students’ shifts from variational to covariational reasoning. In Beswick, K., Muir, T., & Wells, J. (Eds.) Proceedings of the 39th Conference of the International Group for the Psychology of Mathematics Education (Vol. 3, pp. 129-136). Hobart, Tasmania: University of Tasmania

Johnson_PME_2015