This paper compares the effectiveness of two interventions aimed to improve teaching quality and student achievement in Indonesia. The first intervention was the use of education standards, while the second one was the combination of education standards with a teacher improvement program. The study involved 50 schools, 52 teachers, and 1660 students. Teaching quality was measured through classroom observations and student achievement was assessed with a performance test. The multilevel analysis showed student achievement improved only in the second intervention group, whereas the analyses of difference and effect size showed teaching quality in the same group improved only in the first half of the intervention program.