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This Addition Within 20 drill has 40 problems for Grade 2. St Patricks Day theme. Answer key included.
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Max spotted leprechauns stealing rainbow gold coins! He must solve addition problems to unlock the magical chest before they escape.
Standard: CCSS.MATH.2.OA.B.2
Preview
Page 1 — Drill
Page 2 — Answer Key
What's Included
About this Grade 2 Addition Within 20 Drill
At age 7 and 8, your child is developing the mental math skills that form the foundation for all future math learning. Addition within 20 is a critical milestone because it moves students beyond counting on their fingers to using strategies like making tens, counting on, and recognizing doubles. These strategies help children see patterns and relationships between numbers, not just memorize facts. Mastering fluency with numbers up to 20 builds confidence, speeds up problem-solving in real situations—like figuring out how many shamrocks to draw if you start with 8 and add 7 more—and prepares them for two-digit addition and subtraction. At this developmental stage, kids' working memory is growing, and repeated practice with manageable numbers helps them internalize facts automatically, freeing up mental energy for more complex thinking later.
What your student will practice
- Fluently add two single-digit numbers with sums within 20
- Apply counting-on and making-tens strategies to solve addition problems
- Recognize and use doubles and near-doubles to build mental math efficiency
- Decompose numbers to find missing addends in addition within 20
Common mistakes to watch for
Second graders often recount from one instead of counting on from the larger number—for example, solving 14 + 3 by starting at 1 rather than starting at 14 and counting up. Another frequent error is losing track of their count partway through, especially with larger addends, leading to answers like 16 when solving 9 + 8. You can spot this by listening as they solve aloud or watching their fingers; if they're always restarting at one or using both hands to count every single object, they haven't internalized the counting-on strategy yet. Encourage them to point to or touch the larger number first and count forward from there.
During snack time or meal prep, use real food to practice. For instance, ask, 'We have 12 crackers on your plate and I'm adding 5 more—how many will we have?' Start with the larger number and count forward using your fingers or the crackers themselves. This makes the abstract concrete and ties addition to something your child does daily, helping the strategy stick better than worksheet practice alone.