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About this Grade 1 Adding Multiples Of 10 Drill

Adding multiples of 10 is a foundational skill that helps first graders see patterns in our number system and builds confidence with larger numbers. When children learn that 20 + 30 = 50, they're recognizing that we can add the tens place without worrying about ones—a crucial stepping stone toward two-digit addition. This skill develops number sense, helping six- and seven-year-olds understand that numbers are made of groups, not just individual units. In daily life, kids encounter this when counting money, organizing sports equipment into sets of 10, or thinking about time in 10-minute chunks. Mastering multiples of 10 also reduces cognitive load: instead of struggling with mixed numbers, students can focus on one column at a time. This confidence transfers directly to harder addition problems they'll face in second grade, where regrouping becomes essential.

What your student will practice

• Recognize and identify multiples of 10 up to 100
• Add two multiples of 10 using place value understanding
• Explain addition of multiples of 10 using ten-frames or drawings
• Apply adding-multiples-of-10 to solve simple word problems

Common mistakes to watch for

Many first graders add the ones place when they see multiples of 10, writing 20 + 30 = 53 instead of 50. This happens because they haven't yet internalized that the zero in the ones place stays zero. Another common error is treating 20 + 30 like 2 + 3, getting 5 instead of 50—they forget the zero entirely. Watch for students who count on their fingers by ones instead of tens, which wastes time and invites mistakes. If a child writes 20 + 30 = 23 or 20 + 30 = 5, they need to revisit ten-frames or bundles of 10 objects to rebuild place-value understanding.