1. Blanton, M., Brizuela, B. M., Gardiner, A. M., Sawrey, K., & Newman-Owens, A. (2017). A progression in first-grade children’s thinking about variable and variable notation in functional relationships. Educational Studies in Mathematics, 95(2), 181–202.
2. Blanton, M., Levi, L., Crites, T., & Dougherty, B. J. (2011). Developing essential understanding of algebraic thinking for teaching mathematics in grades 3–5. Reston, VA: NCTM.
3. Blanton, M., Stephens, A., Knuth, E., Gardiner, A. M., Isler, I., & Kim, J.-S. (2015). The development of children’s algebraic thinking: The impact of a comprehensive early algebra intervention in third grade. Journal for Research in Mathematics Education, 46(1), 39–87.
4. Boaler, J., & Greeno, J. (2000). Identity, agency, and knowing in mathematics worlds. In J. Boaler (Ed.), Multiple perspectives on mathematics learning and teaching (pp. 171–200). London, UK: Ablex Publishing.
5. Booth, L. R. (1988). Children’s difficulties in beginning algebra. In A. Coxforf & A. P. Schulte (Eds.), The ideas of algebra, K-12: 1988 yearbook (pp. 20–32). Reston, VA: NCTM.