In 1954 I had my school children cut 3 inch circles from old Christmas cards, putting a nice "picture" right in the center of the circle. We laid a 3 inch triangle made of heavy cardboard, (not corrugated board) on the circle and bent up each side of the circle. Ten of the triangles were laid together, one pointing up and the next one down, and we stapled the tabs together. Staple the first on to the last one to create a circle of triangles. Next we stapled five of the triangles together with all the points facing in. That created a round. Made two of these rounds. Now we stapled the rounds of five to the top and bottom of the circle and had a lovely Christmas ball to give to their parents for Christmas.