I must admit that pyjamas, clothing and jewellery seem rather personal (not in a good way ) gifts
I kind of used to think that and the first couple of years ds1 was in school we did the chocolates/candle/smellies set.
And then one year I had to go into ds1's class on the last day of school and caught a glimpse of the table behind the teachers desk and it was FULL of candles, chocolates and smellies gift sets.
It made me think - I think, generally, it's easy for us as parents to forget that the teachers are actually normal people. To most, they're just Mrs Jones who's on the class door every morning that you say hello to - and it's easy to forget that actually Mrs Jones is called Sarah, and she has kids of her own and friends that she goes out with, and sometimes gets drunk and enjoys dancing...or whatever. Mrs Jones is just a person.
All my kids teachers so far have been women in the 25-40 age bracket. Kind of the same as the majority of my team in work. And if I were buying a Secret Santa for a team member in work, I would never give chocolates or a candle or a boots smellies set - because it's so impersonal, it's so dutiful and smacks of 'I had to buy you something so I grabbed this as I couldn't think of anything better'.
If I were buying for a secret santa in work, I would buy earrings, if i'd noticed that she wore earrings daily. I would buy a scarf if i'd seen her arriving in the morning and taking her scarf off. I would buy pajamas if she'd made a random jokey comment on children in need day that she didn't have any matching PJ sets so never mind, she'd make sure she had some next year though (which is what happened with the teacher last year!)
So why not for a teacher? Rather than buying chocolates for Mrs Jones, buy a £5 gift for 34 year old Sarah, who works full time and has three kids and seems to enjoy doing her nails and wearing different earrings and has a lack of PJs.