## Wednesday, February 25, 2015

### Build a chair

who: J2
where: our reception room
when: after swimming lessons

NRICH has a simple activity: use unifix cubes to make a table and chairs. Here's the building material we were supposed to use:

We don't have these cubes at home, so we used TRIO blocks instead. These are 1x 1x n cuboids with a top and a bottom that can be connected. There are also sticks that can connect from any side of  and block to any other side of any other block. these sticks are either 3 or 4 units long.

Here is J1's chair:

After building the set, I asked what he thought of the challenge. He had to solve 2 problems in the construction:
(1) How to deal with the corners where he could only have one block connect to the leg
(2) how to connect the middle of the table so it wouldn't fall through the hole.

His answer was to use a two layer table with corner pieces in the two layers arranged orthogonally. For the middle of the table, he has some sticks along the bottom that support the unattached pieces in the middle (you can see a slight depression in the picture.

Finally, since he knows about the unifix cubes from school, we got to talk about how this construction would have been different using that building set. As always, this compare and contrast discussion was really good for getting him to think about the characteristics of the materials he was using..