For the non-Brits, "sixth-form" means years 12 and 13 of school - equivalent to junior and senior years of high school in the US. The first and second yearsof sixth form are referred to as "lower sixth" and "upper sixth" respectively.
It's a hold-over term from when secondary education (ages 11 and up) started in "first form" and worked up.
It's a hold-over term from when secondary education (ages 11 and up) started in "first form" and worked up.