I just got finished telling Rebecca that for end-of-the-year teachers' gifts, i'm a big fan of the gift card.
Before winter vacation i give Starbucks. End of the year, it's Homesense. that's my "usual."

you really can't go wrong with the gift card.
you don't have to spend a fortune (although 10-15-20 dollars a shot and Emily had 3 teachers and Joshua had 2....it's not cheap either).
you don't have to give it a lot of thought. and they are relatively easy to get. and you don't have to worry about wrapping it.
you know it's something they will use. instead of something they will put on a shelf somewhere with all the other tacky and unusable parent gifts.

I used to think that a gift card was a little cop-out-y of a gift.
it's not quite cash - they don't trust that you will spend your cash wisely, so they make sure you can only spend it in one place.
it's not quite a gift - they wanted to buy you a gift at the Gap, but instead, bought youthis lovely card.

but, in the last few years, i've grown to appreciate gift cards.
they are awesome!
because i am a person who wouldn't spend cash wisely. i'm a person who would stick it in her wallet and end up using it all up, bit by bit, on paying for parking and school trips and frozen yogurt. and at the end of the day, that becomes the suckiest gift ever.
because i am a picky person. if someone buys me something from the gap. 19 times out of 20 i will return it. it's a big problem that i have. i return EVERYTHING. so, a gift card beats me to the punch. there's nothing to return. and i can call you up at the end of the day and say, "hi, mother and father in law, i love the new gym bag and underarmour workout tank you bought me for my birthday!"
see...everyone's happy.