For what to some may seem an esoteric subject, Exoplanet can open their eyes to the possibilities of, literally, other worlds. A very worthwhile use of time, with it you learn not only how many worlds there are in the neighborhood, but also what to expect.
The included, and simple-to-use correlation diagramming feature effectively teaches how to look at a typical large dataset, an invaluable teaching aide for life.
I find this feature particularly fun: change a parameter, study the resulting chart and quickly get an idea of what kinds of worlds are close by. For example, Earth is actually on the smallish scale of the typical planet out there. Many planets in the habitable zone are two, five, ten or more times larger, creating huge surface areas by comparison. Scaled up, imagine if getting to Europe was a 100,000km (33,000 miles or so) overwater journey!
Two thumbs up and five stars, guys!