In this activity, students rolled a 1-20 die and had to figure out what went with their number to make 20. |

We tried dice that had the numbers 1-20, then we used 1-12. Each time students could use the rekenrek to help them build the number on their die and then see what number they needed to go with 20. |

Once they became a little fluent with this we challenged ourselves by figuring out what numbers we would need for combinations to 100. Another one of our standards. Students used place value dice 0-90 to figure out what they would start with. Then we used the large rekenrek to figure out what we needed to equal 100 as shown in the picture below.