This is so true! You've reminded me that there are those academic tests throughout school which the school's credentials are based on. In the UK it was SATs (Statutory Academic Tests) and here in Australia it's the Naplan. I actually recall schools being disappointed that my eldest would be leaving before sitting the tests, so they wouldn't benefit from her scores. As homeschoolers we could still sit the Naplans and it was useful to gauge where they were at with maths and literacy. The school we left to homeschool was eager for my eldest to go back there to sit the Naplan, not realising that it wouldn't count towards their school, but instead fall into the homeschooling category. 😆
The interesting thing was that we chose that school based on the academic scores from these tests and it turned out that they got those scores by cherry picking the students they took on (they had a waiting list) and not through their "superior" education. The local government school turned out to be better at teaching than them. A lot of fast learners left and went to the government school where they were much better stimulated. It was quite ironic.