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Home Intro launchpad Orbiter operations Newton and orbits Build a simulator cabin GPIS School addons Szymon says

 

  Besides the official Orbiter guide, this has to be the most extensive document you can find for Orbiter.

If this were a normal classroom activity book you would have to pay 20$ for each student.

But no ! It's free as all the good things that come with Orbiter.

Get it form Virtual Spacefligh 

 

Also, they made a great document for teachers to explain how Orbiter can be used, a bit of what I'm trying to promote.