It depends on your school. Your student loans never get disbursed straight to you. They go to the school first to pay tuition, and then your school "refunds" the extra money to you. When this all happens depends on A) when your school requests the money from your lender, and B) how long it takes your school to get the money to you via check or direct deposit.
I almost always got mine during the week before school started. Other schools don't get the money out until during the first week or two of school. And I've heard of some schools taking up to a month to disburse funds.