This exploration allows you to travel to the tiny world of DNA. Beginning with the body and ending with the atoms that make up a single DNA base, you'll be able to zoom in to 15 different levels to see DNA's relationship to us as a whole. Along the way you'll also see the intricate bending and winding that takes place within a chromosome, which allows more than five feet of DNA to fit within the nucleus of a tiny cell.
This resource is part of the Biology Links for One Laptop Per Child course which contains units on Exploring Life; The Cell; Genetics; Mechanisms of Evolution; The Evolutionary History of Biological Diversity; Plant Form and Function; Animal Form and Function; Ecology; and Astrobiology.
A covered bridge builder simulation where you can test different covered bridge designs and even build your own! This simulation is accurate and illustrates with different bridge designs and different vehicles the effect of stress on a bridge. You can invent your own truss design, build your own bridge, then test it.
How did scientists figure out the structure of atoms without looking at them? Try out different models by shooting photons and alpha particles at the atom. Check how the prediction of the model matches the experimental results.