# Hundreds Boards

The hundreds board implicitly uses rows of 10 and place value to help in adding two digit numbers.

In grade 3, I usually like students to be ‘weaned’ off this method of adding as it’s highly scaffolded. However, if they haven’t used this tool in grade 2 or a student needs extra support, a bit of work with this can be a lot of use.

 When adding on the hundreds board, a move down one row adds on 10. For example, 32 + 10: When adding on the hundreds board, a move across one column adds on 10. For example, 43 + 1:

Once students understand this step, they can easily use the board for multidigit addition and subtraction.

An interested facet lets some students use different methods. For a question like 37 + 38, a student can either:

 move down 4 rows (+30) and then across 9 spots (+8). move down 4 rows (+40), and then back up two spots (-2).

Transparent bingo chips are a good tool for helping some students keep track of their steps. Laminated hundreds board that students write on with dry erase markers are also useful.

Arrow math replaces jumps of 10 and 1 with arrows. 37 ↓↓↓→→ is 37 + 10 +10 +10 +1 +1, or 37+32.

Resources

 PDF of hundreds board Laminated hundreds boards from Spectrum EducationalI like item # 14520. You can use the non-numbered side for array work for the multiplication facts, and it fits most square tiles or colour tiles also.