Max Rescues the Lab: Subtract Multiples Sprint!

About this Grade 1 Subtracting Multiples Of 10 Drill

Subtracting multiples of 10 is a foundational skill that helps first graders understand how our number system works in chunks rather than counting down one by one. When students master 45 - 10 or 60 - 20, they're learning to think about numbers as groups of tens, which makes mental math faster and builds confidence. This skill directly supports fluency with two-digit numbers and lays the groundwork for addition and subtraction strategies they'll use all year. At ages 6 and 7, children's brains are developing the ability to recognize patterns, and multiples of 10 are one of the most concrete patterns in elementary math. By practicing these problems, students develop automaticity—the ability to solve without counting on fingers—which frees up mental energy for more complex math. You'll notice this skill shows up everywhere: telling time, counting money, and even a scientist organizing specimens into groups of 10 for easier counting.

What your student will practice

• Subtract multiples of 10 from two-digit numbers with fluency
• Recognize that only the tens digit changes when subtracting multiples of 10
• Apply subtracting-multiples-of-10 to solve story problems and real scenarios
• Build automaticity so mental subtraction feels automatic and quick

Common mistakes to watch for

The most common error is students counting backward by ones instead of recognizing the tens pattern. For example, a child solving 37 - 10 might count "36, 35, 34..." instead of seeing that removing one group of 10 simply changes the 3 to a 2. You'll spot this when the answer is off by several numbers. Another frequent mistake is students changing the ones digit by accident, answering 37 - 10 = 27 correctly, but then solving 37 - 20 = 24 instead of 17, losing track of how many tens they've subtracted.