Max Rescues the Flying Carpet: Add by Tens!

About this Grade 1 Adding Multiples Of 10 Drill

Adding multiples of 10 is a cornerstone skill that helps first graders develop number sense and mental math confidence. When children master adding 10, 20, 30, and beyond, they begin to see patterns in our base-ten number system—recognizing that 23 + 10 = 33 follows the same logic as 3 + 10 = 13. This skill reduces cognitive load, freeing mental energy for more complex math later. At ages 6-7, students are naturally curious about "tens" because they're learning to count by tens on their fingers and with manipulatives. Being fluent with multiples of 10 also connects to real-world situations: adding dimes when saving money, counting by tens on a ruler, or adding 10 more pages to a reading goal. This foundation directly supports two-digit addition and subtraction, making future math feel less overwhelming and more achievable.

What your student will practice

• Recognize and add 10 to any one-digit or two-digit number fluently
• Understand that adding multiples of 10 changes only the tens place
• Apply adding multiples of 10 to solve one-step word problems
• Build automaticity with facts like 5 + 10, 24 + 20, 15 + 30

Common mistakes to watch for

The most common error is when students add 10 but change the ones digit instead of the tens digit—for example, saying 15 + 10 = 25 or 23 + 10 = 24. This often happens because children are still building the concept that tens and ones are separate. Another frequent mistake is counting on by ones instead of recognizing the pattern, turning a quick mental math moment into a slow, error-prone process. You can spot this when a child uses fingers or loses track while counting, or when their answers are inconsistent (sometimes right, sometimes off by 1-2). Reinforce by using a hundreds chart or ten-frame to show visually that we're moving down one row, not jumping randomly.