Leo has a Bachelor of Science and a Secondary Teacher Certification in Mathematics and Physics from University of Chile. He taught high school Mathematics in Chile for 4 years, worked as a research assistant in University of Chile and then he joined the Ph.D. Program in Mathematics Education (PRIME) at MSU in Fall 2013, which was also his first year with the PTA project.
His work in Chile was chiefly related with Mathematical Problem Solving. The research group he was part of implemented several professional development courses for primary and secondary teachers related with problem solving. They obtained a Ministry of Education grant (through FONIDE) to investigate the opportunities to learn problem solving and to learn how to teach problem solving in 3 major Chilean universities.
Besides Problem Solving, his (current) interests are related to Mathematics Learning, Development of Mathematical Thinking and Mathematical Knowledge for Teaching.
Hoffman, A., He, J., & Medel, L. (2015, January). Teacher as learner: Reflections from pre-service mathematics teachers. Presented at the Joint Mathematics Meetings. San Antonio, TX. (Link for more details)