Here's what our final looked like:
This is what you'll need:
*black construction paper or poster board
*various colors of tissue paper (save the stuff from gift bags, crinkled tissue paper is fine!)
*disposable cup for the liquid starch
*1/2"- 1" wide paintbrush
*plastic sheeting or a flat garbage bag to protect your work surface
*Elmer's white school glue (or something similar)
E decided he wanted a fishtank and had no interest in cutting one out. So to save some frustration and encourage more crafting time, I did it. You can use long strips of black construction paper or cut out actual designs. I used poster board as it's a bit less likely to bleed and much tougher for small hands. I didn't want to have to cut out another tank. After I took this picture E decided the fish needed seaweed. You'll see that in a second.
I never got a picture of the actual setup/ process before the tissuing was done. You can choose to trace a design with pencil onto a piece of wax paper (mine was the outline of the tank and seaweed) or just randomly place the tissue and add borders later.
Lay your garbage bag or sheeting out, lay your piece of wax paper on top of it, set out little bowls with various sizes and colors of tissue paper, pour a small amount of starch into a cup, and give it a go. Brush some starch onto the wax paper (it will bead up and not look wet), then set tissue paper into it and apply more starch over the top. This will seal it in and give it the stained glass effect. Overlap the pieces until it looks really cool. E had some spots that were 5-6 pieces thick.
Here is his before adding the black pieces.