This site from the Acadia University provides the basic structure of DNA and RNA and a decent compare/contrast between the two.

Describes the steps for how to make a model of DNA using colored polymer clay and wire. Students will gain a good understanding of the structure of DNA by doing this project.

Discover the structure and function of the nucleus of the cell.

Explains what ribose and deoxyribose are, their chemical structure and properties, similarities and differences, their functions, and their biological importance.