Last spring I posted the instructions for making "toothpaste batik" here:
It is such a fun project. This year the paint colors didn't come out quite so vibrant, but I had warned the kids this was a highly experimental project and that however they turn out will be OK in the end. There are so many variables - paint brand, consistency of the toothpaste and lotion, weave of the fabric, etc.
We again mixed $1 store toothpaste and lotion in empty glue bottles (appropriately labeled "NOT GLUE"), and did the "shake-shake dance" to mix them thoroughly. This year we drew the designs in Sharpie on paper which was taped to a piece of tagboard. The fabric was taped over it so there were no pencil lines on the fabric when we traced with the Not Glue. It worked out great. Our paints this year were some Sax Versatemp and Crayola Premium Tempera; the concentrated temperas that were so wonderful last year are no longer made. With lighter colors resulting, we did more outlining & highlighting with colored Sharpie markers and the kids are very happy with their results. Some kids are still finishing up. I'll post a few more when they are done.
By the way - the design motivation was Matisse, but the images chosen to create by the kids are a very "loose" interpretation of the Matisse theme. Some made fish bowls, some used design elements found in the still life, some used organic shapes, etc.