Introducing students to different software packages and applications for use in biology and math courses can be quite a challenge. With that in mind, teachers in these areas will definitely appreciate this rather helpful site from the people at the Mathematical Sciences Digital Library. These particular simulations and tools draw heavily on Microsoft Excel, so users will need to make sure that they also have this program installed. Visitors can click on the "Resources By Category" to access modules that deal with chemical equations in biochemistry, protein analysis, biodiversity, and island biogeography. It is worth noting that other subjects are covered here, including genetics, epidemiology, and ecology.