This is a good rainny day activity for children. Make poster paint: Mix flour and water cook till thick cool ,divide into saucers ,then make colors by adding food coloring an mixing colors ie yellow + red = orange. Next cut potatoes in half and cut designs into them. Have plenty of news paper on table. Stamp the potatoe on the news paper to dry it, then into the poster paint. If there gets too much paint on potatoe stamp just stamp it a few times in newspaper then on to your art paper.Lots of fun they can make designs with the stamps . Stamps can be anything , stars leaves wiggle lines worms what ever you want. Carrots work good too . Bigger kids can do this and use material paint to create colorful T shirts.