Turn words into symbols: write “add 8 and 7, then multiply by 2” as (8 + 7) × 2, use a letter for a number you do not know, and compare without working it out.
Order of Operations & Algebra · Grades 3–5 · 8 levels · Free
Gradeless is free: short math and learning lessons for kids in kindergarten to grade 5, each one starting where your child is. For grown-ups