High school teams usually don't play round robin.
The only time I really played round robin in high
school was at NAQT nationals, which were pretty much
formatted like they play their games on the college level.
In high school most of the tournaments I ever went
to had divisions of teams that played round robin.
After the prelims the teams with the best records went
on to single elim. playoffs. The top seeds are
usually the teams with the best records in the
tournament, not necessarily the division winners, but
sometimes the division winners are automatically the higher
seeds. I suppose it's really just a matter of personal
preference. I don't know if that makes sense or if it is at
all helpful, but there it is.