Books, magazines (not for a gun ), a long letter...pages long from you and people she likes telling her what they are doing day to day and stuff like that.

Post this in the Team forum and you will be ok...GD is a zoo.

If you send cookies, or anything edible, send enough to pass around to the whole squadron.  Because they're going to be eaten immediately at mail call or not at all.    It won't hurt if they're very GOOD cookies, because the DI's are going to have some, too, and good cookies put even a tough DI in a slightly less foul mood.   In fact,  the DI's sort of expect a few batches of cookies to be passed around from time to time.   Yes, that'a  hint.

Reading material isn't going to be a good choice.  I guarantee you that you're never going to be reading anything while in basic except for your manuals and texts.   Except letters from home.   A few photos of what's going on at home are OK and appreciated.

Don't send toiletries.  All that she needs are available to her and I'm sure she already has them.

Really, there's not a lot you can send that will be immediately useful and can be kept.

One thing I would suggest you SHOULD put into a letter is a separate letter addressed to her drill instructors, by name (and correctly spelled!),  thanking them for their service and especially for their having to put up with your little hellion.   Thanks for turning her into a better person who's less likely to have to move back in with the parents,  and so on and so forth.   A slick job of buttering up the DI's,  in short.  

CJ