Max Rescues the Rainbow Gold: Subtraction Quest

About this Grade 1 Subtracting Multiples Of 10 Drill

Subtracting multiples of 10 is a foundational skill that helps first graders work with place value in a concrete, manageable way. When children subtract 10, 20, or 30 from numbers like 45 or 67, they're learning that the ones place stays the same while only the tens place changes. This insight is crucial because it builds mental math flexibility and prepares them for two-digit subtraction without regrouping—a skill they'll use constantly in everyday situations like counting coins, tracking toys, or figuring out how many items are left after sharing. By mastering this pattern early, six- and seven-year-olds develop number sense and confidence with place value concepts that will support all future arithmetic. Plus, recognizing that 57 − 10 = 47 is just as logical as adding 10 helps their brains see math as predictable and learnable, not mysterious.

What your student will practice

• Subtract multiples of 10 from two-digit numbers mentally
• Identify that subtracting 10, 20, or 30 changes only the tens digit
• Apply place value understanding to solve subtraction problems
• Solve mixed subtraction problems with 10-40 within 100

Common mistakes to watch for

The most common error is when children subtract the 10 from both the tens and ones place—for example, solving 35 − 10 as 25 instead of 25 because they miscalculate or lose track of place value. You'll spot this if a child writes 35 − 20 = 13 instead of 15, essentially "subtracting too much." Another frequent mistake is children confusing the direction: they might add 10 instead of subtract, especially if they were just practicing addition in a previous lesson. Look for reversed answers like writing 45 when the problem asks 35 − 10.