It is vitally important that you let your new school know that you are coming right away. Enrollment figures change throughout the year, and especially in the summer when many families move. You will help the school out and maximize your chances of getting your child placed in the most appropriate classes by registering early.
The best solution for this is to go to the school office as soon as you have your rental contract or deed to your new home as proof of address. This will normally determine which school your child is eligible to attend. The requirements of each school may be different, but you will also need: