Max Rescues the Recycling Center: Subtract by Tens!

About this Grade 1 Subtracting Multiples Of 10 Drill

Subtracting multiples of 10 is a cornerstone skill that helps first graders see patterns in our number system and builds confidence with mental math. When children master problems like 35 - 10 = 25 or 50 - 20 = 30, they're learning that the ones place stays the same while only the tens change—a powerful insight that makes larger subtraction feel manageable. This skill directly supports their ability to count money, measure ingredients while cooking, or keep track of toys in a recycling center donation pile. At ages 6 and 7, brains are developing the ability to recognize these patterns and hold multiple steps in mind. By practicing this skill now, students build automaticity that frees up mental energy for harder problems later. When subtraction with multiples of 10 becomes automatic, it creates a strong foundation for second-grade math and reduces anxiety around numbers.

What your student will practice

• Subtract multiples of 10 from two-digit numbers using tens and ones understanding
• Recognize that subtracting tens only changes the tens digit
• Solve word problems involving removal of groups of ten items
• Use base-ten thinking to explain subtraction strategies orally or with drawings

Common mistakes to watch for

Many first graders incorrectly subtract the tens digit from the ones place—for example, answering 34 - 20 = 14 instead of 14. You might also see students who confuse the direction, writing 46 - 10 = 56, or those who subtract both digits carelessly (46 - 10 = 36 becomes 46 - 10 = 12). The clearest sign of confusion is when a child cannot explain why the ones digit stays the same. Watch for hesitation or counting-on behavior when multiples of 10 should feel automatic by mid-first grade.