[1] Marian Small, a proponent of a constructivist approach to mathematical instruction, provides an example of an inquiry-based question from which a three-part lesson could be created: "one bus has 47 students in it; another has 38.
"[4] Students engage in solving math problems individually, in pairs, or in small groups, and "record the mathematical thinking they used to develop solutions".
[1] In this final phase, the teacher oversees the sharing of solutions by students, and may employ other teaching techniques such as "math congress", "gallery walk", or "bansho".
[1] Advocates of the three-part lesson state that students develop "independence and confidence by choosing the methods, strategies and concrete materials they will use, as well as ways to record their solutions".
In Ontario, Canada, where the Ministry of Education has promoted the three-part lesson, the curriculum was changed in the late 1990s in favour of "problem solving based on open-ended investigations rather than memorization".