Max Rescues Dinosaur Eggs: Subtract by Tens!

About this Grade 1 Subtracting Multiples Of 10 Drill

Subtracting multiples of 10 is a foundational skill that helps first graders recognize patterns in our number system and build mental math fluency. When children master 23 – 10 or 45 – 20, they're developing number sense and understanding how place value works—skills that directly support all future math learning. At ages 6 and 7, students are naturally drawn to patterns, and this concept leverages that developmental strength. Being able to subtract tens quickly reduces cognitive load, freeing up mental energy for more complex problems. This skill also appears constantly in real life: calculating change at a store, figuring out time remaining on a timer, or determining how many toys are left after giving some away. Students who can subtract multiples of 10 fluently gain confidence and approach bigger math challenges with less anxiety.

What your student will practice

• Subtract multiples of 10 from two-digit numbers with automaticity
• Recognize that subtracting 10, 20, or 30 only changes the tens digit
• Apply subtraction of multiples of 10 to solve one-step word problems
• Check answers using inverse operations or counting strategies

Common mistakes to watch for

Many Grade 1 students subtract tens from the ones place instead of the tens place—for example, answering 34 – 10 = 24 as 34 – 10 = 13. This happens because they're still consolidating place value and may not fully understand that the tens digit and ones digit are separate. You'll spot this error when a child's answer has the ones digit removed or altered. Another common mistake is confusing subtraction with addition, especially when working quickly through a grid. Some children also struggle because they're relying on counting backward by ones instead of recognizing the tens pattern, making the process slow and error-prone.