This lesson uses shapes/symbols to represent a missing value in a mathematical equation.

For this assessment, students must decide if there is more than one way to add up numbers.

For this activity, students listen to a story to solve a problem. Students count out 10 mice and place some inside the jar and some outside the jar and use pictures, numbers, or words to show the many ways the ten mice could be arranged.

This is a teacher resource that shows activities for students to decompose numbers less than or equal to 10 into pairs in more than one way, e.g., by using objects or drawings, and record each decomposition by a drawing or equation (e.g., 5 = 2 + 3 and 5 = 4 + 1).

For this task, students look at a picture of a number and fingers to come up with a number sentence that matches the picture.

Students solve addition word problems with numbers up to 18 in this interactive resource.

Students work with a partner to determine whether the product is even or odd when multiplying an odd number times an even number, an odd number times and odd number, and/or an even number times an even number.

Students work with a partner to determine whether the sum is even or odd when adding an odd and even number, an odd and odd number, and/or an even and even number.

In this engaging interactive, students must click on the frogs so they will jump in the water before they cross the finish line. Students will use subtraction to determine how many frogs jumped in the water.

In this interactive, students practice fluently multiplying within 100 by solving multiplication facts to 12 as they compete against students from around the world.

For this interactive, students select from one of five levels to practice addition facts to 9 by selecting the penguin with the correct answer to the equation.

For this assessment, students are told that Justing just picked a variety of oranges from different trees. They must decide how many oranges Justing picked altogether.

This interactive reinforces students' ability to count back and to understand the "take away" model of subtraction. Students select starting numbers from 10 to 20. As a group of rabbits appear, students are asked how many will remain if a certain number jump away.

Students roll a die to determine the number of rows for the array and roll the die a second time to determine the number of counters to put in each row of the array. Next, students draw the array and write an equation to express the total number of counters as a sum of equal addends.

For this interactive, students click on the missing number to complete the number sentence.

Students use square tiles to copy and extend a given pattern in addition to recording and numbering the value of each square in the sequence. Students identify the difference between the numbers in consecutive squares describing any patterns they notice and tell what they think the value of the 6th and 10th terms in the sequence will be, explaining their thinking.