It is common for those that have trouble jumping to position themselves too far back (to stay farther away from the expected crash), resulting in flying with the front too high and, quite possibly, causing the crash they were trying to avoid.
You want to land with both wheels at the same time or, if anything, your front wheel touching down just before the rear. On a down-sloped landing, that means flying with your front wheel lower that the rear...not a comfortable position at first, but very natural once you get the hang of it.
I would suggest working on landing a little on the front wheel (and on the gas). Once you get comfortable with that on small jumps, then work your way up.
The single best thing to keep from getting kicked sideways in the air is to squeeze the bike with your lower legs and knees all the way up the jump and into the air.