**Number Expanders**

**Focus: **Consolidate the *renaming *idea by using patterns in the written number system to flexibly rename large collections of base 10 material (eg bundled straws, MAB blocks etc).

**How: **See *Number Expanders BLM and * instruction sheet in order to see how these devices are made and folded in order to flexible rename any given three digit number. Number expanders can be used in conjunction with the Straw Bundling or MAB sculpture activity. Once students have determined a total in either of these activites, they can represent that total on a number expander and then practice modelling the different renaming combinations indicated by the expander. For example, if there are 324 straws (arranged as 3 hundreds, 2 tens and 4 ones), these can also be rearranged as 324 single straws, 3 hundreds and 24 single straws or 32 tens and four single straws.

*Download Number Expanders instruction sheet*

*Download Number Expanders BLM *