Running over catcher

If there was no imminent play at the plate then the runner does not have to slide. if the catcher is in the basepath/blocking the plate it is an obstruction

If it was a malicious contact play it is up to the umpire to make the call

Under NFHS rules, the runner must avoid contact either by sliding or by running around the catcher. The penalty is, runner is out and potentially ejected from the game. An ejection often carries the penalty of also missing the next game as well.

If the runner is trying to avoid the catcher and the catcher obstructs him, then home plate could be awarded. Thus, catcher obstruction does not excuse a runner who initiates contact. The runner carries the obligation to avoid collision. After all, he's the one who's typically heading full speed while the catcher is standing there, dead duck, often watching the ball while only seeing the runner out of the corner of his eye.

If the runner is trying to avoid the catcher and the catcher initiates contact, the call would be obstruction and a potential ejection of the catcher.

It all depends on how the umpire saw it. If the situation occurred as you describe it, the call was very bad indeed and would merit a coach's call to the chief of umpires. But note, oftentimes parents' eyes deceive them. Never underestimate the inability of parents to be objective in how they remember a play going down.

NFHS rules basically seek to avoid injury as the paramount goal. Who scores or doesn't, or who wins or doesn't, is a secondary consideration.