I'm certainly no expert, but...
I have enjoyed beautiful success with a McClusky product available from Ace Hardware
called GymSeal. It's a single
part flexible coating commonly used on basketball courts and gymnasiums and has remained in fine condition on our teak
& holy sole for the past three years under severe conditions. It comes in gloss or satin finish. $17 USD / quart.
And I reckon a school
gymnasium suffers far more abuse than any boat
ever will - provided a competent skipper
keeps her off the rocks.