## Grouping and Grazing

Pre-K-2
Standards:
Math Content:
Number and Operations

Help the alien spaceship move cows into corrals by counting, adding, and subtracting. This activity helps children learn grouping, tally marks, and place value. As they master counting, they can move on to adding and subtracting two-digit numbers.

A video tutorial is also available to demonstrate the use of this applet.

General Tools

Menu brings you back to the home screen from any activity.

Move allows you to move cows in the workspace.

Group corrals cows into groups of 5 or 10, depending on the activity. Select the tool, select the appropriate number of cows, and then select the tool again to use.

Ungroup removes cows from a corral.

Check allows you to input the correct final number of cows. C clears the window, and the checkmark submits the answer.

For every correct answer, you will receive a barn at the bottom of the screen.

Count by 5s

Count cows by corralling them into groups of 5. To do this, click on the cows until 5 are purple and upside down. Then, click Group. Repeat this step until you can no longer group 5 cows together. Loose cows should be moved into the upper area separately using the Move tool.

Tally counts cows as you group using tally marks. It may be hidden at any time using the green arrow at the bottom of the Tally window.

New displays a new problem at any point.

Check

Count with Me counts cows by selecting first all groups of corralled cows and then all loose cows. The count will also be displayed in the Tally window, if shown.

Count Alone lets users input the number of cows into a calculator. The count will also be displayed in the Tally window, if shown.

Count by 10s

Count cows by corralling them into groups of 10. To do this, click on the cows until 10 are purple and upside down. Then, click Group. Repeat this step until you can no longer group 10 cows together. Loose cows should be moved into the upper area separately using the Move tool.

New displays a new problem at any point.

Check

Count with Me counts cows by selecting first all groups of corralled cows and then all loose cows. The count shows tens and units separately to reinforce place value.

Count Alone lets users input the number of cows into a calculator.

Begin by moving all cows from the top two areas down to the bottom sum area to combine them. Then, group loose cows by 10s if there are enough loose cows. This is the same as carrying using the traditional addition method.

Any Numbers displays a new problem at any point using numbers selected by the computer.

My Numbers displays a new problem at any point using numbers you select. Value must be between 0 and 20.

Subtract

Begin by moving the subtracted number of cows into the lower left area. You may need to ungroup cows to move the correct number. This is the same as borrowing using the traditional subtraction method. Make sure cows are corralled in both the upper and lower left areas if they can be. When you click Check the remaining cows will be moved to the lower right area.

Any Numbers displays a new problem at any point using numbers selected by the computer.

My Numbers displays a new problem at any point using numbers you select. The value in the first box must be between 0 and 40. The value in the second box must be at least 0 but less than the value in the first box.

Count

• Before starting a problem, can you estimate how many groups you will have? Now, try it. Was your estimate correct? After doing the activity many times, does your estimate get better?
• Is it faster to count the total number of cows before you group them or after you group them?
• When counting by 10s, how does the written number relate to the final grouping of cows?