Max Conquers the Carnival: Subtract-By-Ten Challenge!

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 master problems like 35 − 10 or 50 − 20, they're learning that we can remove entire groups of tens without changing the ones place. This skill strengthens mental math ability and prepares them for two-digit subtraction without regrouping. At ages 6–7, children are developing the abstract thinking needed to understand that 10 is a unit we can work with, just like we do with single numbers. By practicing these problems, students discover a predictable pattern: only the tens digit changes. This early success builds the number sense and confidence they'll need for more complex subtraction strategies in later grades.

What your student will practice

• Subtract multiples of 10 from two-digit numbers with automaticity
• Recognize that subtracting tens only changes the tens place
• Solve word problems involving removal of groups of ten
• Explain subtraction of tens using tens and ones language

Common mistakes to watch for

Many first graders incorrectly subtract from the ones place, turning 43 − 20 into 43 − 2, or they confuse which digit to change and write answers like 25 instead of 15. Watch for students who count backward by ones instead of by tens, which leads to errors and wastes time. Some children also struggle when the ones digit is larger than the number being subtracted, mistakenly thinking they need to regroup. A quick check: ask the child to explain what happens to the ones place in 67 − 30—if they mention the 7 changing, gently redirect them back to the pattern.