Max Rescues Holi Colors: Subtract by Tens!

About this Grade 1 Subtracting Multiples Of 10 Drill

Subtracting multiples of 10 is a foundational skill that helps first graders see patterns in our number system and build confidence with larger numbers. When children learn that 45 − 10 = 35, they're discovering that we can subtract whole tens without breaking apart the ones—a concept that makes mental math faster and easier. This skill directly supports the way we count by tens on a number line and organize numbers into groups, which are critical for understanding place value. By mastering this pattern, six- and seven-year-olds develop number sense they'll use for decades of math ahead. Real-world moments—like counting down 10 days until a birthday or subtracting 20 minutes from playtime—become opportunities to practice this pattern. Children who recognize "subtract 10, the ones stay the same" can tackle two-digit subtraction with much less frustration, setting them up for success in second grade and beyond.

What your student will practice

• Subtract tens from two-digit numbers with automatic fluency
• Recognize that subtracting 10 keeps the ones digit unchanged
• Apply tens-subtraction to solve real-world problems involving groups of ten
• Build confidence handling numbers beyond 20 without counting on fingers

Common mistakes to watch for

The most common error is when students try to subtract the 1 from the tens digit instead of the whole 10—for example, saying 34 − 10 = 33 by only moving down one number. Another frequent mistake happens when the ones digit changes: a child might solve 42 − 10 and answer 31 instead of 32, accidentally renaming the ones. You'll spot these patterns when a student consistently changes the ones place or subtracts just 1 instead of 10. Ask them to show you using base-ten blocks or to explain which digit should change, and they'll often correct themselves immediately.