This interactive incorporates engaging 3D-models of viruses that students can click on to rotate and view from different angles. In the process they will learn about the criteria that scientists use to classify viruses, the characteristics of different viruses, and the global prevalence of viral infections. A link to an illustration of the relative sizes of viruses provides an opportunity to discuss scale and units.

Source: Virus Explorer | HHMI BioInteractive

Pretty cool, especially the ability to show relative sizes.