I found this interesting:-

Quote
All groups who are overage-for-grade, whether they have been redshirted or retained, have higher participation in special education services for learning disabilities, cognitive disabilities, and emotional disabilities.

Given that red shirting occurs primarily in higher SES families that clearly game the system, I wonder whether the higher incidence of special Ed service recipients among overage-for-grade kids is caused by the families gaming the system further by getting their kids classified to get extra time on tests etc...

Become what you are