He has a B.S. in Applied Mathematics from UCLA, an M.Ed., and a Ph.D. in Education from UCLA. Lager has helped develop, facilitate, and evaluate the English Language Development – Mathematics Content (ELD-MC) institute, an in-service professional development model for California mathematics teachers and paraprofessionals of ELs grades 3-8 focused on integrating academic English language proficiency with algebraic instruction. As the Mathematics Assessment Coordinator for the Vermont Department of Education, he brought EL needs to the fore when crafting large-scale assessment policies and reviewing large-scale mathematics items with colleagues from New Hampshire and Rhode Island to inform the development of the New England Common Assessment Program (NECAP) Mathematics Assessments.