Native Americans became masters at extracting the natural dyes contained in vegetables and plants. By purchasing just a few readily available products from the supermarket, you can create vegetable dyes just like Native Americans used.
With adult supervision, children can learn to make dyes from different vegetables and then tie-dye a T-shirt or piece of fabric using their homemade dye. Carrots, red cabbage and beets are good vegetables to use for dye, and children can experiment by creating different colors.
Shred the vegetables using a grater or food processor, then place them in a pan and cover with cold water.
Simmer on low heat for up to half an hour, and then strain the colorful liquid from the vegetable matter.
To dye fabric (it will only work for natural fibers like cotton and silk), soak it in the dye solution overnight, then rinse well.
Children can experiment by using more or less vegetable matter, combining different-colored dyes and leaving the fabric in the dye for shorter or longer time periods to create different colors
Check out this video that shows a similar project: http://bit.ly/a8lzUu