2 parts white glue (Elmer's)
1 part Sta-Flo liquid starch

Mix well. It needs to dry a bit before it is "workable". It may not work well on a humid day. Store in an air-tight container.

Note: If you use Elmer's school glue instead of regular white, it does not bounce or pick up pictures but it makes a gooey delight that kids will love. Use on a smooth surface.