I think it's a silly site. Basically, all you are comparing is how well the students performed in a test on one day of the school year. How well students perform in tests has NOTHING to do with how 'well' the teachers teach, or how 'good' a school is. A school with above average results can just mean that most of the students take tests well. A school with below acverage results doesn't mean that the students aren't learning, or that teachers are ineffective. It can just means that the students don't take tests well.

Which I'm pretty sure is the 'outrage'.

Definitely take the ratings with a grain of salt.
I think you hit the nail on the head.

Whilst I agree with parents having more knowledge in the their choices they make for their children, these league tables and this website is the wrong way to go about it.

I think parents would be better informed if they speak to other parents at the school to see how they view the school, speak to the children that attend the school to get their opinions, and speak to staff at a school.

This puts so much pressure on students. Imagine how those kids feel who were down the bottom of the league tables that have been created feel. Way to lift their already fragile self esteems. Your results are the worst in the state, etc.