Thanks for all of the input on the pros and cons of sports. In the end we decided not to use the pros and cons approach, instead we focused on the overall impact of what our county calls secondary athletics.
Secondary athletics in Montgomery County Maryland have done a great job of growing gender and ethnic diversity in athletics. However, the county has no such equivalent for STEM. So we argued that if the county trully wants to grow both diversity and participation in STEM that they should take all of the things that work well for athletics and apply them to STEM.
Here is a write up that captures more details.
http://team1389.com/discussed-making...ort-with-mcps/