All I did was color the water with neon green food coloring, and put up some craft foam butterflies on the wall. You can buy these from Dollar Tree, or cut your own out of your own craft foam. All you need to do is get them wet and they magically stick to the walls of the tub. Drying is easy too and they can be used again and again for baths, or used again for a craft.
Now for the bath paint. We went to a place the other day where we got to see lots of different types of butterflies, so that experience is very fresh in my daughter's mind! We took home a brochure from there that has several different butterflies on it with pictures and names. Well after looking at that yesterday I had decided we needed to make bath paint to create these gorgeous creatures ourselves on our shower walls! So, I used a tray with multiple sections from Dollar Tree, and made black, neon blue, neon green, neon pink, and orange bath paints. To make the paints you just need shaving cream and food coloring. Squirt a little shaving cream into each spot on your tray, or into each bowl, whatever you're using. Then you squirt some food coloring into each one (one color each) and mix that in one by one, rinsing paint brush or makeup brush in between each color.
These were the colors of some our favorite butterflies, so with these we could make them! The orange and black for example made the Orange Tiger butterfly. The black was needed a lot for body and antennae of the butterfly, so that's why I put that color in the middle. I also sat our plastic Monarch Butterfly that we got from the gift shop on the paint for pizzazz.
My daughter was so excited about this bath. I'm sure your kids would be too!