Crystalline Entity wrote:
Where MoS may have taken shortcuts is that we don't see the Kents realize Kal-El is a superpowerful alien, and we don't see Clark leave home for good.
They know he is an alien.
"You're the answer, son. You're the answer to 'Are we alone in the universe?'"
They also know about his x-ray vision, heat rays, super hearing, super strength, etc., and Martha learns about his ability to fly later on.
While we don't see the actual moment of Clark leaving home, we see the argument between 18-year-old Clark and Jonathan about him wanting to leave and be his own man (and not a farmer), immediately followed by Jonathan's sacrifice in the tornado, which is presumably the final catalyst for his departure.