Origami · folding only · Growing · about 15 minutes

Open Square Box

No scissors · No glue · No adult help needed

Square of origami paper, 200 x 200 mm (8 x 8 in)

Finished

Blue dashes: valley fold (toward you). Pink dash-dot: mountain fold (away from you). Thick line with scissors: cut. Yellow: glue.

Start. Put the square down like a diamond, with one corner pointing up and the white side facing up.
1. Fold and unfold: Fold the top corner down to the bottom corner. Press, then unfold.
2. Fold and unfold: Fold the left corner over to the right corner. Press, then unfold. The creases cross in the middle.
3. Valley fold: Fold the top corner and the bottom corner to the middle, where the creases cross.
4. Valley fold: Fold the left corner and the right corner to the middle too. This square with four flaps is called a blintz.
5. Fold and unfold: Fold the top edge down to the middle line, press and unfold. Do the same with the bottom edge.
6. Fold and unfold: Fold the left edge to the middle line, press and unfold. Do the same with the right edge. Now there is a grid of creases.
7. Unfold: Unfold the top flap and the bottom flap, so two points stick out again. Keep the left and right flaps folded.
8. Valley fold: Fold the left side and the right side in to the middle along the creases.
9. Open: Lift the two folded sides up so they stand straight. These are the first two walls of the box.
10. Push: Lift the far end up to make the third wall. Its two corners fold inward along the creases; press them flat against the wall.
11. Valley fold: Fold the point over the top of the wall and down into the box, until its tip touches the middle of the bottom.
12. Put together: Lift the near end up the same way: push its corners in, then fold its point over the wall and down into the box. Press the bottom flat.

If something goes wrong

The walls are crooked or the corners do not meet. The four corners must meet exactly in the middle in the blintz step, and every grid crease must be sharp before you lift the walls.
The corners will not fold inward. Pinch each corner from the outside along its diagonal crease and push it in gently while you lift the end.
The box opens up again. Press the two points flat against the bottom inside the box; they hold the walls in place.