Just because this always comes up - why /shouldn't/ teachers get gifts?
I work a volunteer job alongside teaching and, while it doesn't always happen, it's a regular occurence that customers give gifts as a thank you for excellent service. Anything from flowers to a few bottles of wine.
While teachers get paid for doing a job, so does everyone else and it's nice to receive a little thank you on top - who wouldn't appreciate it?
I don't expect gifts, but I was moved to tears at one I received from a student this year, who was excellent in working out mine and colleagues' tastes and managed to give a little perfect something to all of us. I keep all the cards, too.
OP, I have to say, better no gift than money. In some schools, all monetary gifts have to be handed in to Finance, so the teacher might not be able to keep them anyway. But also, it feels wrong. However, chocolates, biscuits, nice tea - all very much appreciated.