Here is a clever paper magic stunt. You can make a very pretty little square box, so securely fastened that it cannot easily be taken apart.
Use rather heavy paper if you have it, but ordinary note paper or wrapping paper will do. Cut out a perfectly square piece and fold it from corner to corner in both directions.
Then fold down the corners to the center, as in Fig. 1.
Now open the sheet and fold each corner down to the center of the crease just as in Fig. 2.
After creasing all these lines, open out again and fold corner A (Fig. 2) to the center of crease B.
Again, open up the paper, and do the same with the other three corners.
All these folds have been made correctly, when you open up the sheet, there should be seven diagonal lines crossing it in each direction, as in Fig. 3.
Cut out the eight darkened triangles, and then cut the slits along the heavy lines as indicated.
Take one of the lower corners and, without creasing, bend the two loose points together.
Pass them from below through the slit in the diagonally opposite corner and open them out again.
Smooth out the bends and do the same with the other two corners, being careful to see that the two loose squares are folded inside the box.
The box will then appear as in Fig. 4 with the top securely fastened. To open it, release the outer flap, thus opening out the sides.