The purpose of this activity is to help students learn groupings with 10. For example 10 and 2 make 12; 10 and 3 make 13.
Recall groupings with 10, for example 10 and 2 make 12; 10 and 3 make 13.
- Show the students how to make the calculator show “plus ten”. Do this by pressing the keys: “+ 10 =” . Then, when any number is entered, followed by the equals key, the calculator will display 10 more than the number entered. For example, if “5 =” is entered, the calculator will display “15”.
- Enter the number “8” into the calculator and say:
We have put the number 8 into the calculator. When we press the “=” key it will show us 8 plus 10. What will that be?
- Once students have given their answers, show them that the answer from the calculator is 18.
- Continue as a whole group in this way, or have students work in pairs with one student entering the numbers into the calculator and the other identifying the “plus ten” fact.
Note: using single digit numbers will help students learn groupings with ten, or the “teen” numbers. Larger numbers can be entered into the calculator once students are confident with these.
This activity can be repeated in a similar way to help learn groupings with 5.