Surf for More Math
Lesson 1 - Adding and Subtracting Whole Numbers
To encourage your child to have fun on the Web while learning about Adding and Subtracting Whole Numbers, here are some games and interactive activities they can do on their own or in pairs.
Use mental math strategies to calculate sums and differences.
Student Book pages 106-107
Instructions for Use
Adding and Subtracting Mentally lets your child practice using mental math strategies to add and subtract.
To use Adding and Subtracting Mentally, select a topic - either addition or subtraction. Then select the level of difficulty - green is easy, yellow is difficult, and red is the most difficult. Click the 'Begin!' button to load the first of ten questions. Input the answer in the text box and press 'Enter'. The tally on the screen shows your results.
Base Block Addition lets your child practice addition with and without regrouping.
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 in 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 a 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.
Adding Whole Numbers prompts your child to use a paper and pencil to add 4-digit numbers.
To use Adding Whole Numbers , click the 'Start Addition' button. Using paper and a pencil, place the number to be added below the first number so that the thousands, hundreds, tens, and ones places are aligned. Draw a line under the bottom number. Add the bottom place digits from the top ones and regroup where necessary. When your child has finished adding the numbers, input the answer in the text field and click 'Check'.