Subtract 4-digit numbers

💡 How it plays and why it helps

In 7047 − 604, the hundreds column asks for a regroup from a place that holds zero hundreds. Subtract 4-digit numbers gives one subtraction per card, a four-digit number minus a three-digit one, with new numbers on every card, ten per round. Your child types the difference in this Grade 5 game; each answer is checked, and the hint walks through the method.

Column subtraction works place by place: line up the digits, subtract the ones, then the tens, then the hundreds, and regroup 1 from the next place whenever the top digit is smaller. That is the hint, nearly word for word. Regrouping is just renaming: 7 thousands and 0 hundreds become 6 thousands and 10 hundreds, and 10 − 6 leaves 4.

Taking the smaller digit from the bigger is the classic slip. In 7047 − 604, the hundreds column reads 0 − 6, and flipping it to 6 − 0 gives 7643. Ask, "Can you take 6 hundreds from 0 hundreds without trading?" Then trade one thousand. Praise it: "You traded before subtracting."