Maybe she is wanting something that she can give to the kids at the end of the year.
My DD 5th grade teacher had the kids write a letter to themselves, we had to send in 2 envelopes with our current address and the address of a relative in case we moved. She is holding onto them until they graduate high school and then she is mailing them out to the students.
My DD's 7th grade Teacher did this and it was pretty neat this summer when she got hers! She had actually forgotten about doing it until the letter came in the mail. Her Teacher had put a letter in with them reminding them when they had written the letter and wishing them the best as they went to school and on with their lives and how much she had enjoyed knowing them. She also said that it was a joy to look back at the letters and see how some had known what they wanted and did just that and how some had changed and grown etc. I didn't even know they had done this but it was great.