Every question on this sheet has an easy way round, and the page shows it: the sum, the rewrite that makes it easy, then blanks for the numbers that are left. These free printable worksheets mix all six strategies on one page, for grades 3 to 5.
If they get stuck
The answer key prints on a separate page.
Mental math is not a separate kind of arithmetic. 99 × 8 is still 792, and 37 + 48 + 63 is still 148 — but written as (100 − 1) × 8, or as (37 + 63) + 48, both become sums a child can finish without a pencil. The skill being practised is spotting which rewrite turns a hard question into two easy ones.
Each question is written the way the strategy is taught, one equals sign per line: the question, the rewrite, the easy part, the answer. The rewrite is printed, because at this stage it is the lesson; the numbers after it are the child's. Switch to Drill and the same questions ask for the answer alone, which is the recall that comes after the method.
One question off this sheet, worked a step at a time — with a sentence saying what just happened and why.
Mental math strategies, step by step