Max Rescues the Presidential Monuments: Adding Tens Quest

About this Grade 2 Adding Multiples Of 10 Drill

Adding multiples of 10 is a cornerstone skill that builds your child's number sense and mental math fluency during second grade. When students master this concept—recognizing that 20 + 30 is simply "2 tens plus 3 tens equals 5 tens"—they develop flexible thinking about place value that makes larger addition problems feel manageable. This skill directly supports their ability to add two-digit numbers without always needing to count on their fingers. At ages 7 and 8, children's brains are developing stronger working memory, and practicing multiples of 10 teaches them to "chunk" numbers into friendly groups rather than processing individual ones. This foundation prevents frustration later when tackling regrouping and subtraction. By Presidents' Day, many second graders have seen how skip-counting by tens (like counting dollar bills) connects to this exact concept.

What your student will practice

• Identify and combine groups of tens without counting individual ones
• Recognize patterns when adding multiples of 10 mentally
• Apply skip-counting by tens to solve addition equations
• Build confidence with two-digit addition using tens as building blocks

Common mistakes to watch for

The most common error is when students revert to counting by ones instead of recognizing tens as complete units—for example, solving 30 + 40 by counting 1, 2, 3... 70 rather than thinking "3 tens and 4 tens make 7 tens." You'll spot this if a child's pencil is moving slowly across problems, their lips are moving (silent counting), or their answers are inconsistent even on identical problem types. Another frequent mistake is ignoring the zero—writing 3 + 4 = 7 when the problem shows 30 + 40, suggesting they're not yet anchoring tens to place value.