Max Rescues the Robot Factory: Subtraction Quest

About this Grade 1 Subtracting Multiples Of 10 Drill

Subtracting multiples of 10 is a foundational skill that teaches first graders how numbers work in groups of tens, which is the building block of our entire number system. When children master subtracting 10, 20, or 30 from numbers like 45 or 67, they're learning that you can remove whole groups without having to count down one by one. This skill dramatically speeds up their mental math and builds confidence with larger numbers they'll encounter later. At ages 6 and 7, children's brains are developing the ability to see patterns and work with abstract groups rather than just individual objects. By practicing these problems, students strengthen their place value understanding—knowing that the tens place and ones place are separate and that subtracting tens doesn't affect the ones digit. This prepares them for two-digit addition and subtraction, and eventually multiplication and division. Real-world applications appear constantly: making change at a store, measuring ingredients in cooking, or tracking scores in games.

What your student will practice

• Subtract multiples of 10 from two-digit numbers fluently
• Recognize that subtracting tens leaves the ones digit unchanged
• Connect subtraction of tens to removing groups of ten objects
• Solve word problems requiring subtraction of multiples of 10

Common mistakes to watch for

Many first graders incorrectly subtract the tens digit without thinking about the ones place, so they'll write 45 - 20 = 25 as if the 5 disappeared. Others confuse which digit to change and might write 45 - 20 = 44, touching both digits when only the tens place should shift. Watch for students who revert to counting down by ones instead of recognizing the pattern—this shows they haven't yet grasped that tens are removable units. If you see hesitation or pencil-counting, your child likely needs to manipulate physical tens (like ten-sticks or dime-stacks) before moving to abstract problems.