Subtracting 2 and 3-digit numbers using base 10 blocks, 100 grids, 100 charts, number lines, expanded form, mental math strategies, and more. Subtracting 2 and 3-digit numbers in grades 2 and 3 takes time for many students to master, especially when regrouping is required. Establishing a good understanding of place value is necessary before moving on to operations. Base 10 blocks are great for understanding place value and for simulating subtraction. Representing numbers with base 10 blocks allo