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Materials:
Procedure:
For example: if the there are 2 tens rods and 3 unit cubes, they will write a 2 in the ten's column and a 3 in the one's column (They may also identify the number on the 100s chart to help them connect the number with standard written numbers) 2. Cover the base ten blocks with a sheet of paper, and show a new amount of base ten blocks. For example: show 5 unit cubes
4. After students are done figuring their answers, remove the paper and count blocks focus on the number of tens rods and unit cubes. Notes: start simple by adding an amount of unit cubes that do not go into the next ten's place. Progress to adding greater numbers of unit cubes (such as 27 + 7) and tens rods as students get more adept.Challenges:

