Take an empty coke bottle and fit it into a balloon. For adding a bit pop to this idea you could also decorate your balloon with beads, studs or design them with markers and glitters- after fitting the coke bottle.
Indoor Activities for Kids: Homemade Lava Lamps. Vegetable oil, a about of the water bottle, then water. 10 drops of food coloring. Then take a alkaseltzer tab and break it into 4 pieces. Drop one in at a time and wait for each to dissove!