Master Subtraction with the "Think Addition" Strategy! Help your students bridge the gap between addition and subtraction with this comprehensive 150-problem bundle. Designed specifically for Grade 1 (CCSS 1.OA.B.4), this resource uses a proven scaffolding approach to build confidence and mental math fluency. Instead of just "taking away," students will learn to find the Missing Partner—transforming tricky subtraction into familiar addition problems! 📦 What’s Included ✔️ Missin