Max Collects Winning Card Combos: Adding Tens Challenge

About this Grade 1 Adding Multiples Of 10 Drill

Adding multiples of 10 is a cornerstone skill that helps first graders see patterns in our number system and build confidence with larger numbers. When children recognize that 20 + 30 is really just 2 tens plus 3 tens, they're developing number sense that makes all future math easier. This skill bridges the gap between single-digit facts they've already mastered and the two-digit addition they'll tackle soon. By age 6 or 7, children's brains are ready to spot these patterns—it's the perfect time to help them see that numbers aren't random but follow logical rules. Mastering multiples of 10 also builds mental math speed, which means less reliance on counting on fingers and more confidence solving problems quickly. Think of it as learning the "shortcuts" that mathematicians use every day.

What your student will practice

• Recognize and identify multiples of 10 up to 100
• Add two multiples of 10 using tens place understanding
• Apply place-value thinking to solve addition problems mentally
• Explain why 30 + 40 uses the same thinking as 3 + 4

Common mistakes to watch for

The most common error is when first graders add multiples of 10 by treating them like single digits—for example, solving 30 + 20 as if it were 3 + 2 and getting 5 instead of 50. Another frequent mistake is forgetting to regroup the zero: a child might write 30 + 20 = 5 instead of 50, losing the tens place entirely. You'll spot this if your student gets the "tens digit" correct (3 + 2 = 5) but forgets the zero or doesn't understand why 50 is the answer. This often happens because the child hasn't yet connected the physical tens blocks or groupings to the written numbers.