Two-Digit Addition Within 100: Grade 2 math

What this covers

Two-Digit Addition Within 100 is taught in Grade 2 (age 7 to 8) as a topic to introduce. It sits in the Number strand.

Worked example

Difficulty scale

The sheet generator offers five difficulty settings for this topic.

1. Adding a 1-digit number to a 2-digit number without bridging ten (e.g., 23 + 4)
2. Adding a 1-digit number to a 2-digit number with bridging ten (e.g., 28 + 6)
3. Adding a multiple of 10 to a 2-digit number (e.g., 45 + 30)
4. Adding two 2-digit numbers without regrouping (e.g., 42 + 35)
5. Adding two 2-digit numbers with regrouping across ten (e.g., 47 + 38)

Common mistakes

• Adding tens to ones by concatenating digits without place value alignment
• Forgetting to add the bridged ten when sum of ones exceeds 9

Curriculum links

Indicative matches to Common Core State Standards. Check wording and codes against the official document.

• 2.OA.A.1 Use addition and subtraction within 100 to solve one- and two-step word problems.
• 2.NBT.B.5 Fluently add and subtract within 100 using strategies based on place value and properties of operations.