During a field goal, if the ball hits the ground and bounces through the uprights and above the crossbar, is it still good despite hitting the ground first?
No. Rule 11 Section 4 Article 1 states:
Article 1 Successful Field Goal. A field goal is scored when all of the following conditions are met:
(b) After the ball is kicked, it must not touch the ground or any player of the offensive team before it passes through the goal.