Typical waste of demolition or renovation projects is Plywood. Often it just ends up in a waste container.

This I'ble will show you how to upcycle this Plywood into a comfortable childrens chair. Basically, the chair is constructed like a box, which makes it simple, strong and easy to enlarge or reduce depending on the amount of wood available or the size of your kid. It does not need any screws as it is almost entirely glued.
Furthermore, you can change the shape of your side panles and thus design a wide variety of models.

Step 1: Design & Materials.

You only need a few basic dimensions of your kid to design this chair (see sketch for the design process). Once you have these dimensions you can make whatever shape of the side panels, because the method of construction is allways the same. For comfort reasons, I have rotated the entire design 10 degrees.

Further you will need:
* 2 side panels: two sheets of Plywood (50 x 50 cm)
* Seat panel: 1 sheet of plywood (35 x 35 cm)
* Back panel: 1 sheet of Plywood (35 x 65 cm)
* small wooden beams to support the back panel and the sat panel (not shown)
* glue
* small nails
* 3 construction beams (they are only used to make a rigid frame while the glue dries. Make sure they are shorter than the width of the seat panel (!).

IMPORTANT! The strenght of the seat is determined by the accuracy of the chair and the glue bond. Therefore, the width of the seat panel and the widt of the back panel should be identical and very accurate (straight!)

Step 2: Measure and Cut.

Picture 1
Screw the two large plates (side panels) together at the corners.

Picture 2
Set out the dimensions of the side panel of the seat.

Picture 3
Using a saw, cut out the profile.

Picture 4
Set out the measures of 1 specific corner (radius 10 cm approximately).

Picture 5
Cut the radius and release the screws. Now you have two identical panels.

Step 3: Glue It Together.

Picture 1
Glue and nail the wooden beams in place on both side panels (according to the dimensions of the sketch in step 1). These beams are to support the seat panel and the back panel. Make sure that the back panel can slide between the beams.

Picture 2
The other panel should be made the same.

Picture 3
Assemble both side panels with the 3 temporary construction beams Use the same screw holes you have used previously). Apply glue to the beams of the back panel and to the sides of the back panel itself. Slide the back panel in place until it touches the floor.

Picture 4 & 5
Apply glue to the seat panel beam and the side of the seat panel and slide it into place. Wipe any residual glue away, tighten the construction beams, add weight to the seat panel and attach two large clamps if you have these..

Picture 6
Once the structure is dry, remove the construction beams and round off the rest of the corners.

Picture 7
Although originally not planned, I made a small bookshelf below the seat panel with some leftover wood (principle is the same as described above).