I cut mine the same way Honeyman. And, the preferred method is to make the cuts after the boxes are assembled. Gives you plenty of material to hang on to so you can control the stock. I've never once had a problem with kickback. And that's not to say that it hasn't occured, or started to, that I couldn't very quickly get it under control.
Disclaimer, if you are not the handyman, woodworker or new too the whole concept of woodworking and table saws and don't have a clue what kickback is all about. Get with someone to give you learning, use a router, or like these other fine folks suggest. Use cleats! You can get yourself in a lot of hurt in a hurry!!!!
"Success is not final, failure is not fatal: it is the courage to continue that counts." Winston Churchill