Curated OER
Add and Subtract within 100
Practice problem solving with 10 word problems. Learners are encouraged to draw to solve each of these simple addition and subtraction word problems. Note: There are typos and some of the problems are awkwardly worded.
Mangahigh
Mangahigh: Number: Number Pairs Up to 100
Students explore the concept of number pairs by working through an online tutorial and then attempting a ten question quiz that increases in difficulty as questions are answered correctly.
Khan Academy
Khan Academy: Add Within 100
Practice adding two-digit numbers. All numbers in these problems are 100 or less. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.