Max Rescues the Castle: Subtract by Tens!

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 groups of ten. When children master 50 - 20 or 60 - 30, they're not just memorizing facts—they're building mental math flexibility that will serve them for years. This skill connects directly to place value understanding, which is central to all future arithmetic. At ages 6-7, students are developing the ability to recognize patterns, and multiples of 10 provide a perfect, repeatable pattern. Real-world applications abound: counting coins, tracking scores in games, or figuring out how many stickers remain after giving some away. Children who become confident with this concept gain independence in solving problems and develop the number sense needed for addition and subtraction with larger numbers.

What your student will practice

• Subtract multiples of 10 from two-digit numbers with automaticity
• Recognize and explain the pattern in subtracting tens without counting on fingers
• Apply subtraction of multiples of 10 to solve word problems
• Decompose two-digit numbers using tens to check subtraction work

Common mistakes to watch for

Many first graders subtract the tens digit but forget the ones place stays the same, writing 45 - 20 = 25 correctly but then incorrectly solving 45 - 20 = 2. Watch for students who line up numbers carelessly or count backward by ones instead of recognizing the tens pattern. Some children also confuse which number to subtract from, especially when a smaller multiple of 10 appears first. Asking students to explain using ten-frames or base-ten blocks quickly reveals whether they understand the concept or are guessing.