Addition (sums to 20)

Before handing out the worksheet, briefly introduce the concept with a short oral warm-up or a visual model on the board. Encourage students to talk through their thinking as they work: "What strategy are you using? How do you know that is right?" After completing the worksheet, review any missed problems together and discuss the reasoning rather than just the answer. For extra support, let students use manipulatives or draw pictures alongside the written problems. These two-digit addition worksheets work well as daily practice, homework, or a focused review activity.

These two-digit addition worksheets for 1st grade give students the structured, hands-on practice they need to build confidence and fluency. Students work through a range of problem formats, from visual models and diagrams to written equations and word problems, so they encounter two-digit addition from every angle. Each worksheet is designed to build on prior knowledge while introducing the level of challenge appropriate for 1st grade. Practicing two-digit addition at this stage strengthens the mathematical foundations that support more advanced concepts in later grades.

This worksheet is designed for 1st Grade students (Ages 6-7), aligned to Common Core standard 1.OA.1. It can also be used as review for early students at the next grade level or as an introduction for advanced students.

Yes. This worksheet works for homeschool, classroom, and tutoring settings. Print individual pages for targeted practice, or print the full set as a packet. Works great as a morning warm-up, independent center activity, or fast-finisher task.

By the end of first grade, students should fluently add within 10 (CCSS 1.OA.C.6) and solve addition problems within 20 using strategies like counting on, making ten, and decomposing numbers. They should also add within 100 using place value understanding (1.NBT.C.4).

Start with adding a two-digit number and a one-digit number, then progress to two two-digit numbers. Use place value understanding: add the tens first, then the ones. Base-ten blocks and place value worksheets make this concrete before moving to abstract equations.

Key strategies include counting on from the larger number, making a ten (e.g., 8+5 becomes 8+2+3), using doubles (6+6=12) and near-doubles (6+7=6+6+1), and decomposing to known facts. Worksheets that practice each strategy separately help students build fluency.