This document discusses the importance of developing students' mental math and estimation skills. It notes that the Saskatchewan curriculum emphasizes teaching both computational fluency and helping students understand the mathematical concepts underlying procedures. While practice is important for developing fluency, it should not come at the expense of exploring concepts. Finding the right balance is key. The document provides examples of formative assessment strategies like "commit and toss" and "fist to five" that teachers can use to check students' understanding without putting them on the spot. It also shares online resources for virtual manipulatives and interactive applets that can engage students.