Distro Astro is a Linux-based operating system for astronomers. http://www.distroastro.org/
Distro Astro contains software useful for classroom use. It includes desktop planetarium software such as Stellarium and Cartes du Ciel for simulating the position of the stars and planets in the sky, with built-in databases of celestial objects that let you find information about any object in the catalogs.
It includes software to calculate and predict astronomical events, such as XEphem, Astronomy Lab 2, AstroCC Coordinate Converter, and command line tools ephem and aa. It also includes Meteoracle for meteor showers, GPredict for artificial satellites, XTide for the tides, and Accurate Times for Islamic calendar calculations.
Gravitational simulators like Planets and Gravity allow you to play with masses, velocities, and orbits. Another program called Gravit is compatible but not included.
Programs like Where is M13? and StarPlot Viewer allow you to visualize the positions of stars and galaxies in 3-D space. Virtual Moon Atlas lets you study the surface of the moon using textures and overlays. OpenRocket lets you design model rockets.
The Digital Universe Atlas developed by the Hayden Planetarium of the American Museum of Natural History is compatible with Distro Astro but not included. Many other educational tools on astronomy and space science that are compatible with Ubuntu 14.04 Trusty LTS will also run on Distro Astro.