The Finish Your Self Junior chair by Dutch product designer, David Graas is a DIY project that children will enjoy making with some adult help. The corrugated cardboard chair is simply built up with some basic slitted shapes that are simply slotted together. It doesn't look that comfortable but children probably won't care because it is so much fun to sit on a chair you made yourself. A small cushion might be a good idea.
The best part about this product, besides the quality time spent with children, is that the chair is completely recyclable once it is outgrown. This is one piece of furniture children would love to draw on with full parental consent!