A thoughtful gift for a teacher can be something that shows your appreciation and gratitude for their hard work and dedication. You could consider a personalized gift such as a mug with a special message or a photo frame with a picture of you and your teacher together. A heartfelt card or handwritten note can also be a great way to show your appreciation. If you know your teacher's interests or hobbies, you could also consider a gift related to that. Overall, the most important thing is to show your appreciation and make sure the gift is thoughtful and meaningful.