Max Collects Sunny Beach Treasures: Adding Tens Quest

About this Grade 1 Adding Multiples Of 10 Drill

Adding multiples of 10 is a cornerstone skill that bridges your child's understanding of place value and mental math fluency. At ages 6-7, children are building the number sense needed for two-digit addition, and mastering patterns like 20 + 30 or 40 + 10 trains their brains to think in groups rather than counting individual ones. This skill reduces cognitive load—instead of counting 1, 2, 3... all the way to 50, your child recognizes that 10 + 40 is simply "one ten plus four tens." On a sunny day at the park, a child who can quickly add tens can mentally calculate that two groups of 10 blocks plus three groups of 10 blocks equals five groups of 10. These early patterns create the foundation for regrouping, subtraction, and multi-digit computation in second grade and beyond.

What your student will practice

• Identify and skip-count by 10s fluently up to 100
• Add two multiples of 10 mentally without counting by ones
• Recognize the pattern that 2 tens plus 3 tens equals 5 tens
• Apply multiples-of-10 addition to word problems with concrete contexts

Common mistakes to watch for

Many Grade 1 students add the tens digit but forget the zero at the end, writing "5" instead of "50" for 20 + 30. Others revert to counting by ones, touching each number and slowly adding up, which defeats the purpose of recognizing the pattern. Some children also confuse the words—they hear "thirty" and lose track of the place value, thinking they're working with single digits. Watch for hesitation when problems cross decades (like 60 + 40) or when the answer reaches 100; this signals the student isn't yet grasping tens as a unit.