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About this Grade 1 Subtracting Multiples Of 10 Drill

Subtracting multiples of 10 is a fundamental bridge skill that helps first graders move beyond counting on their fingers toward flexible mental math. When children master 45 − 10 or 60 − 20, they're learning that the ones place stays the same while only the tens change—a pattern that makes arithmetic feel logical rather than mysterious. This skill connects directly to real life: counting back lunch money, tracking remaining days until a birthday, or figuring out how many blocks remain after cleaning up. Developmentally, six and seven year olds are gaining the abstract thinking needed to see numbers as collections of tens and ones rather than just individual units. Fluency with multiples of 10 also builds confidence and speed, reducing anxiety around subtraction problems they'll encounter throughout second grade and beyond.

What your student will practice

• Subtract multiples of 10 from two-digit numbers accurately
• Recognize that only the tens digit changes, not the ones
• Solve one-step word problems involving subtraction by tens
• Build mental math fluency with facts like 50 − 20 and 80 − 30

Common mistakes to watch for

Many first graders mistakenly subtract 10 by removing one digit entirely, writing 25 − 10 = 5 instead of 15. Others confuse the tens and ones places, changing the ones digit by accident—like solving 34 − 20 as 34 − 2 = 32. Watch for students who count down one by one instead of jumping back by tens, which shows they haven't internalized the place value pattern yet. If a child is still using fingers or objects when all peers have moved to mental math, they may need concrete tens-and-ones practice before drilling.