Homemade Mod Podge: White school glue + A jar with twice the volume of your glue. Squeeze the glue into the jar. Fill the glue bottle with water. Seal and shake. Now squeeze that watery stuff into the jar. Seal and shake. Go decoupage something.
coat rack idea for kid's room. Now, if you want to make the hooks more sturdy for say, heavier coats, I would drill small screws from back of board into back of animal heads for extra support if glue doesn't hold as well.