Sometimes all you really need is a template to get you started. That's what this is... a template. I've left some sections the way I've written them for my parents, others I've left blank for you to put together.
Be VERY detailed. That way parents have a resource and SO DO YOU! When a parent contacts you with a question, you can refer them back to your handbook. The handbook diminishes the number of phone calls, e-mails, and notes about the same information.