I'm no mathmatition an breaking orbit is quite difficult. I'm trying to get the NASSP Apollo en route to the moon but it just won't break Earth orbit. It goes up till about 1000km and then it starts comming back down. I exhaust my fuel before I can even get anywhere. How do I do this?

Which NASSP version?Anyway the best way to do it is burn prograde (forwards) to increase speed. This will end up increasing the altitude more than any other way. You have to do this at a precicely timed position and time. even 4 seconds too long/early/late/short will end up nowhere near the moon (well near, but too far to correct a capture/free return trajectory)Try This Tutorial too. Takes a lot of practice, but if you do everything in this tutorial, you should be able to come out alrighthttp://www.jdkbph.com/Paitence and Practice. The secret to Success here.

Have you tried it in one of the default Orbiter ships like the Delta Glider or the Shuttle A? Add ons like NASSP are a lot more complex and use different instruments than the default. Actually to get to the Moon you don't break orbit from Earth. All you do is raise your orbit so that it intersects the Moon's orbit. I haven't tried the NASSP add on but in the default ships I get into orbit and align planes then I use the Transfer MFD to set up a burn that will give me an intersection. When the time comes I just burn prograde until my actual orbit matches the hypothetical one I planned and I'm on my way.