1. You can buy a bouquet for your teacher, but it's not fresh flowers. I don't know if you've heard of cartoon bouquets. There shouldn't be many of them on the market, but you can find them online. They're not ordinary flowers. They'll be gone in two days. In addition to cartoon rose bouquets, there are also bunny, hello kitty, and Doraemon ones. There are many styles, all of which are popular cartoon characters. You can find them with a search. They're very practical and ornamental.
2. You can buy a cup for your teacher. Of course, it's not an ordinary water cup. It should be very popular now. There's a photo on the surface of the cup, which should be laser-printed, not pasted on it anyway. Then pour hot water into it, and as the water level rises, the photo will appear little by little. But the prerequisite is that you have to get a photo of your teacher. If it's a photo with her husband, it might be even better. The price is not very expensive. You can check it out yourself.
3. Make a pair of sleeves for your teacher yourself. The teacher will produce a lot of chalk dust every day when he/she is teaching. You can wear this for class without worrying about it getting dirty. But the style must be nice and novel.