This project will develop an intervention to support the teaching and learning of proof in the context of geometry. This study takes as its premise that if we introduce proof, by first teaching students particular sub-goals of proof, such as how to draw a conclusion from a given statement and a definition, then students will be more successful with constructing proofs on their own.

- Cirillo, M. & Hummer, J. (under review). Proof as problem solving: How do students solve secondary geometry proofs?
*ZDM*.* - Cirillo, M., & Hummer, J. (2019). Addressing misconceptions in secondary geometry proof.
*Mathematics Teacher, 112*(6), 410-417.* - Cirillo, M. (2018). Engaging students with non-routine geometry proof tasks. In P. Herbst, U. H. Cheah, P. Richard, & K. Jones (Eds.)
*International Perspectives on the Teaching and Learning of Geometry in Secondary Schools*, (pp. 283-300). Cham, Switzerland: Springer.* - Cirillo, M. & May, H. (in press). Decomposing proof in secondary classrooms: A promising intervention for school geometry. Paper accepted to ICME-14.*
- Cirillo, M. & Pelesko, J. A. (in press).
*Mysteries, Models, and Mathematics: Mathematical Modeling in Secondary Classrooms*.