Subtraction Strategies 5-Week Unit Workbook | Math Skills | Grades 1-3 | No Prep | Ontario + CCSS - 15-lesson structured practice unit Make subtraction strategies click! 15-lesson workbook with ready-to-use daily practice, built-in scaffolding, answer keys, and Google Slides compatibility. Ontario + CCSS aligned. Build lasting subtraction strategies fluency with this structured 5-week workbook. Each week scaffolds difficulty with increasing number ranges, worked examples, format variety, and spi