Origami d10 Die

	Start with 5 pieces of square paper. Each square will make two sides of the 10-sided polygon.
	Fold each square in thirds, both ways.
	Fold in half, then cut along the crease, making two pieces.
	Fold one of the new pieces in thirds along the previous creases, making a sort of tube. Then fold the top layer in half, then unfold it, to mark the center line.
	Make a fold from the center top to the left side at the crease. Make another fold from the right side at the crease to the left bottom corner.
	Refold those folds inside the tube. These will make the slots.
	Make a fold from the top center to the right side at the crease. It will extend a little past the other fold. Fold that bit under. Make another fold from the left side at the crease to the bottom center. These will be the tabs that will be inserted into the slots.
	Fold the other half of the square the same way. Except switch left and right, so that it will come out as a mirror image of the first piece.
	Cut and fold the other 4 squares the same way.
	Take 5 pieces that are the same. Insert the long tab of one into the long slot on another. Continue until all 5 are connected.
	Then complete the circle by connecting the first piece to the last one.
	The other 5 pieces make up the bottom of the polygon. Insert the short tab of one piece into a short slot of the top, at the same time inserting a short tab from the top into the new piece's short tab. Continue adding the pieces to the bottom, connecting them to the top, and connecting them to each other with the long tabs and slots.

This model is a modification of David Brill's Stellated Dodecahedron.

There are diagrams for creating many more polyhedra here.