It's been a disaster in the few places it's been tried. Chile (since abolished) and currently in Sweden. It very obviously causes the school corps to cut costs by various means that have a negative societal impact.

For example by giving undeservedly high grades that upper-middle class seemingly happily accept to get their kids into high-status high education. These grades then conveniently becomes part of their marketing.

An even more sinister example is their willingness to actively segregate their schools to have "easy", as in cheap, students that don't require as much resources (like actual teachers) as people - on average - from less privileged backgrounds.