Make Your Own Privileged Planet
NASA-Ames Research Center has produced an online simulation game called AstroVenture that allows kids to try to design a habitable planet. After they pick half a dozen parameters, the game tells them whether humans could live there or not.
This is a cute feature that, with caveats, could be useful for parents and teachers. The main problem is that it is too simplistic. The planet-construction dialog asks what kind of star you want to put your planet around, how close to the star, how big it is, whether it has water and a few other things. These are fine and good, but not enough. It doesn’t discuss many other factors that could be show-stoppers: crustal composition, type of atmosphere, place in the galaxy, eccentricity of the orbit, size and distance of moon, and much more. Still, kids may be surprised to find how few of their choices actually work.
Of course, the Astrobiology folks behind AstroVenture want kids to learn early how to speculate about life in outer space. They want to help kids exercise the power of imagination and speculation, since these are prerequisites for Darwin Party membership later. All that aside, learning that only a small subset of possible planets are even in the ballpark for life is a worthwhile lesson. For junior high and older, use this in conjunction with the film The Privileged Planet.