With respect to the other replies, fixed/not fixed is a personal choice. I recieved the basic SAK on my 6th birthday (you know, blade, file, scissors), and promptly lost it that weekend on a camping trip with my father. I still carry a SAK as my backpacking knife, with a sheath however... The ONLY time in 28 years I've been cut with a knife was 4 months ago, with a locking folder! Since a non locker can only fold on you if you bang the top of the blade, you must be screwing up to cut yourself.

Anyway, yeah, I think a cheap SAK would be a great choice. Gadgets are fun, it's small sized so it's not intimidating, shiny metal (as opposed to a bead blasted or black blade), and they come in enough colors that she'll probably find one she likes.