To dye the noodles:
Put about a Tbsp. of rubbing alcohol and as many drops of food coloring as you want into a baggie(the more food coloring you use the darker the color). Let it sit in the baggie for about 10 minutes, flip the bag over and let it sit for another 10 minutes. Spread the noodles out onto wax paper and allow time to dry (usually at least an hour). The coloring will bleed through the wax paper onto your counter so I usually put a few layers or newspaper under the wax paper.
This method also works for coloring clothespins, craft sticks, etc.
Mrs. Larremore (creator of ChalkTalk....awesome blog) is having a linky party. Check out her page for more fun math ideas!