The importance of understanding how motivational beliefs may be influenced by teacher’s instructional practices is paramount. Motivational beliefs of students define their engagement in classroom learning activities. This study looked into the influence of varying classroom practices on students and mathematics motivational beliefs and mathematics achievement. These motivational beliefs include goal orientation belief, control belief, efficacy belief, and interest and value belief. Simultaneously, it also looked into the relationship between motivational beliefs and classroom practices which included two constructivist practices. These classroom practices are the interactive social group (ISG), the individualized highly independent and accountable group (HIAG), and the traditional lecture group (TLG). A true experimental design – equivalent groups pre- and post-test design – was used. Results showed that teaching approach influence student motivational beliefs and have significant effects on achievement measures. Moreover, among these motivational beliefs, mathematics efficacy and goal orientation beliefs were found to have significant effects on conceptual knowledge achievement.