"Although a drawing is nice, a model is even better." Using pipe cleaners and four different colored beads or pieces of colored straws you can make a model of DNA. Each different color represents one of the four different nucleotides. Two long pipe cleaners are the edges of the ladder and the beads or straws are strung on the rungs of the ladder, which are made of small pieces of pipe cleaners which are then attached to the long pipe cleaners. Don't forget that you need to be careful about paying attention to the bead color combinations; adenine only links to thymine and cytosine only links to guanine. Once the ladder is completely put together, hold the ladder up and twist it to make the characteristic double helix shape.