San Mateo-Foster City School District is a school district in San Mateo and Foster City, California. It consists of twenty schools: three middle schools, fourteen elementary schools (TK/K–5), and three schools with all grades (K–8). With a total enrollment of approximately 12,500 students, it is the largest school district in San Mateo County. Students in the San Mateo-Foster City School District continue on to the San Mateo Union High School District.