School physical education (PE) aims to develop students' knowledge and skills for lifelong participation in physical activity (PA). Unfortunately, many PE teachers report that motivating students is a significant challenge. The purpose of this study was to explore PE teacher perceptions about the effectiveness and acceptability of three self-determination theory-based motivational strategies on students' PA, motivation, and learning during PE lessons. Thirteen PE teachers from five schools in Western Sydney, Australia, participated in this study. We carried out semi-structured post-lesson interviews with PE teachers to gather information about the perceived effectiveness and acceptability of the three intervention strategies and whether these were sustainable teaching methods: (1) explaining relevance; (2) providing choice; and (3) complete free choice. Analysis of interview data revealed that teachers believed each strategy successfully enhanced student PA, enjoyment, motivation, and student learning. The findings also showed that our motivational teaching strategies were acceptable when embedded within certain PE contexts. Overall, the results have implications for future pre-service and in-service PE teaching practice.