Lesson 3 – Adding 2-Digit and 3-Digit Numbers

To encourage students to have fun on the Web while learning about Adding 2-Digit and 3-Digit Numbers, here are some games and interactive activities they can do on their own or in pairs.

Goal
Add 2-digit and 3-digit numbers using pencil and paper.

Builds Upon
Student Book pages 152-154

Instructions for Use

Vertical Addition lets students practice addition with and without regrouping.

To use Vertical Addition, input the answers in the text fields beginning with the ones column. Click ‘Check’ after adding the ones column, and input any numbers to the tens column that are carried over. Continue to input the answer in the tens column. Press ‘Enter’ each time after inputting a number. When students have completed the questions, click the ‘Next’ button to add a different question.

Base Block Addition lets students practice adding 2-digit and 3-digit numbers.

To use Base Block Addition, drag a base block into a column to the left. If your child moves a block one column to the right, it breaks apart to show the exchange, for example, a 10-long for ten units. To group pieces to exchange the other direction, click and hold the mouse key down while dragging a rectangle to "lasso" the pieces. The newly grouped object can then be dragged into the next column.

To complete a preset addition problem, select base 10 and click on the ‘Next Problem’ button. Group any pieces and drag them into the next column. Start with the 1s column and work to the 1000s column. The addition solution will appear on the left.

To add the blocks together to create your own problem, click on the ‘Create Problem’ button and then use the blue buttons at the top to enter blocks above and below the dashed line. As long as there are two numbers correctly represented in the specified base, the addition problem will appear on the left. To solve it, click on the ‘Begin Problem’ button and then on any of the blocks in the workspace.