Help! How to make a DNA model?

I have a biology examination project to make a dna model.
Well i know the components, but I’m really really out of idea on what materials i should need.

My teacher said that using wires are boring, and I will get less score if I use wires again.

So i really need other materials which I think would not waste time (I’ll still have to do it at home) because the exam takes only one and a half hours.
And also materials which are easy to find so that would no necessary mess. It should be also easy.

maybe links to other websites?