OLSAT test. What is this?

Administration is telling us it's for placement in AP classes and other since it measures "ability". It becomes part of my kid's "portfolio". TAG teacher says it's not for placement. Teacher says it actually helps determine where to put a child in class without teacher "bias".

We plan to opt-out of Dumber Balance, I mean Smarter Balance later this year, but we are not sure what to think of this one. Supposedly, it has nothing to do with school funding or teacher evaluation.

Thoughts? I can't find much on the web about it except very-pro or very-con.