National Geographic's Mapmaker Interactive is a free map creation tool that doesn't require students to have any kind of registered account in order to make great thematic maps.
Some of the excellent tools offered in Mapmaker Interactive include measuring distances, adding placemarks, layering information, and switching between base map layers. All maps created in Mapmaker Interactive can be printed. They can also be shared online. In the video embedded below I provide an overview of the features in National Geographic's Mapmaker Interactive.