Immersion Program Entry and Exit Policies

I'm looking for examples of entry and exit policies for immersion programs from throughout the country.  We are launching three partial immersion programs in the fall of 2012 in my district and we are working on policies now so that we can effectively place students into programs and monitor "withdrawals" from programs in the best possible way.  We have one example but would like to see others so that we can craft a policy that will work best within our district understanding that every child is different.  If you'd be willing to share, you can email documents directly to me at fulton.lynn@gmail.com or respond here with attachments or a weblink to online copies of your policies.

Thanks!

Lynn