3rd Grade Addition Within 100 Worksheets and Activities

In this addition worksheet, students add a 2-digit and two 1-digit numbers in their heads. It’s great mental math practice that helps build number sense and confidence with multi-step addition. Worksheet instructions: Find the sum for each problem below.

In this worksheet, students add one 2-digit and two 1-digit numbers in their heads. It’s great mental math practice that helps build number sense and confidence with multi-step addition. Worksheet instructions: Find the sum for each problem below.

In this addition worksheet, students "complete the hundred" by finding the missing addend in addition equations where the sum is 100. Students are encouraged to solve these exercises mentally, without writing down intermediate steps. Worksheet instructions: Find the missing number in each equation.

In this worksheet, students "complete the hundred" by finding the missing addend in addition equations where the sum is 100. Students are encouraged to solve these exercises mentally, without writing down intermediate steps, to build number sense and fluency. Worksheet instructions: Find the missing number in each equation.

In this addition worksheet, students practice finding missing addends in problems that combine a 2-digit number with a 1-digit number. The goal is to build fluency and confidence in mental math by solving these problems quickly and accurately. Worksheet instructions: Find the missing number in each equation.

In this worksheet, students practice finding missing addends in addition problems that combine a 2-digit number with a 1-digit number. The goal is to build fluency and confidence in mental math by solving these problems quickly and accurately. Worksheet instructions: Find the missing number in each equation.

In this addition worksheet, students practice finding missing numbers in equations with sums up to 100. This worksheet helps reinforce basic addition skills and boosts mental math abilities. Worksheet instructions: Find the missing number in each problem below (no regrouping needed).

In this addition worksheet, students practice finding missing numbers in equations with sums up to 100. This worksheet helps reinforce basic addition skills and boosts mental math abilities. Worksheet instructions: Find the missing number in each problem below (no regrouping needed).

In this addition worksheet students practice addition within 100 by finding missing numbers in equations. It reinforces number relationships and place value. Worksheet instructions: Find the missing number in each problem.

This addition worksheet helps students practice addition within 100 by finding missing numbers in equations. It reinforces number relationships and place value. Worksheet instructions: Find the missing number in each problem.

This addition worksheet helps students practice adding 2-digit and 1-digit numbers within 100 (with carrying). Designed to improve mental math skills, it encourages kids to solve problems quickly and accurately through repeated practice. Worksheet instructions: Find the sum for each problem.

This addition worksheet helps students practice adding 2-digit and 1-digit numbers (with carrying). Designed to improve mental math skills, it encourages kids to solve problems quickly and accurately through repeated practice. Worksheet instructions: Find the sum for each problem.

This mental math worksheet helps students practice adding 2-digit and 1-digit numbers with carrying. Designed to improve mental math skills, it encourages kids to solve problems quickly and accurately through repeated practice. Worksheet instructions: Find the sum for each problem.

This addition worksheet helps students practice adding 2-digit and 1-digit numbers with carrying. Designed to improve mental math skills, it encourages kids to solve problems quickly and accurately through repeated practice. Worksheet instructions: Find the sum for each problem.

This word problems worksheet focuses on simple addition. Students are presented with real-life situations where they need to calculate the answers to word problems using addition. Worksheet Instructions: Read each problem carefully, then write your answers in the space provided.

This worksheet focuses on simple addition word problems. Students need to focus on solving real-life situations using addition. Worksheet Instructions: Read each problem carefully, then write your answers in the space provided.

This word problems worksheet focuses on simple addition. Students need to focus on solving real-life situations using addition. Worksheet Instructions: Read each problem carefully, then write your answers in the space provided.

Worksheet instructions: Find the missing numbers in each circle by adding the given numbers. If you find it easy, try to figure out the answers mentally (without writing down the intermediary steps).

Worksheet instructions: Find the missing numbers in each circle by adding the given numbers. If you find it easy, try to figure out the answers mentally (without writing down the intermediary steps).

Worksheet instructions: Add or subtract to find the missing number for each problem.

Worksheet instructions: Find the missing number for each problem. If both boxes are empty, fill in both numbers.

Worksheet instructions: Find the missing number for each problem. If both boxes are empty, fill in both numbers.

Worksheet instructions: Find the missing number for each problem. If both boxes are empty, fill in both numbers.

Worksheet instructions: Find the missing number for each problem. If both boxes are empty, fill in both numbers.

Worksheet instructions: Find the missing number for each problem. If both boxes are empty, fill in both numbers.