Hi E.~
That's the kind I did use when I was a teacher. I'd have a cup of coffee before the kids came and I had it in a travel mug because if it tipped over, it wouldn't spill on the papers that were on my desk.
So... to answer your question, I personally wouldn't need another one because I had 3 or 4 travel type already. Extras were nice in case I left one in the car or at school.
I have plenty of water bottles too, but some teachers may need one and there are some cute ones that are insulated. I think you are sweet to give it some thought, but if you just include a gift receipt, that would be nice so in case the teacher doesn't need or want another one, she could return it and pick something else out.
The best gifts I received were the letters of appreciation. The letters that specifically stated what they appreciated about me were worth more than any gift that cost money. It was still nice to get a general type of letter such as.....
Thank you Mrs. P. for being a great teacher. Sammy really enjoys being in your room. Have a Merry Christmas.
BUT.... the letters that were DETAILED such as...
Thank you Mrs. P. for being a loving, caring and organized teacher. Sammy has already blossomed in first grade and I know you have had a lot of impact in making that happen. He is now excited about going to school and making friends. He talks about you at home and I can tell he really enjoys having you for a teacher. May you have a wonderful holiday season. Love, The Smith Family
The gifts that warm my heart so much were the letters from parents, as well the students, an ornament and homemade cookies or muffins. NOW every teacher will not like that because some don't want the extra calories or maybe worry if the bakers hands were clean, or don't want another ornament. Haha....with mugs and teacher stationary, it seemed like one more just made more clutter, but with ornaments it was different. I could pull it out of the box once a year and look at it and have it bring back memories of that specific child. Some teachers may only want certain colors on their tree or have a certain theme for their tree, BUT I would love a variety or ornaments. I STILL put up a few from former students and I haven't taught school for 10 years!