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Math - Memory Work
LevelPrimary
Age4 - 5
Materialstwo set of bead bars 1-9
one set of bead bars 1-10
wooden + sign
wooden = sign
small felt mat

This activity teaches the child how to add single digit numbers together.
I've put instructions for doing this lesson the traditional way first, but I think it works much better when done with math blocks instead. The pictures showing this are further down.

## Presentations

### Sums up to 10

1. Set up three bead bars as shown, two with five bead bars, one with ten.
2. Move the 2 bead bar down from the first bead stair.
3. Move down the 1 bead bar from the second bead stair.
4. Count the combined bead bars.
5. Move down the 3 bead bar for the answer from the third bead stair. Compare it with the 1 and 2.
6. Lay out the bead bars with the symbols in between.
7. Do some other +1 equations to make sure the child gets the idea.

### Sums greater than 10

1. Set up three bead stairs, two with nine bead bars, one with ten.
2. Move down one of the longer bead bars from the first bead stair, then a longer bead bar from the second bead stair. Place them end to end.
3. Count the total beads and lay out the answer from the third bead stair consisting of a ten bar and the appropriate smaller bead bar.
4. Lay out the bead bars with the symbols in between.

## Material

### Mortensen Blocks

I've found that this activity works much better using Mortensen Math (or Math-U-See) blocks rather than the traditional bead bars. At the very least, it would be better to use bead bars that are fused together and do not have the little wire loops sticking out at the ends.
For example, to show that 2+1=3 it is much easier to see the equivalence with the blocks than with the bead bars:

The improvement is even more apparent with larger sums:

The child doesn't need to count to see that the two addends together are the same as the answer, it can be plainly seen.

#### Sums Less than 10

The procedure for doing addition with sums less than ten is the same with the blocks as with the bead bars:

#### Sums Greater than 10

The procedure for doing addition with sums greater than 10 is similar but with one important difference.

1. Set up the material in the same way as with the bead bars.
2. After you have laid out the two addends end to end, count only up to ten, then stop. Get the 10 block and lay it beneath the addends.
3. Count the remaining blocks that stick out past the 10. Find the block that fills the remaining space.
4. Lay out the blocks with the symbols in between.