I learned a lesson about this a few years back when my first group of 5 had 2 children graduating to JK and I started advertising and interviewing in January. NEVER DO THAT!!! I got all the shoppers and that's when I perfected my prescreening techniques.

But April/May is a good time to start. If you sign them up too early then you're just stressed that they will actually show up in Sept. Also, I came up with the policy of writing Non Refundable on the deposit and don't allow it to be applied to fees when I'm holding a space in the future.