Wow! That is a tough one. In our area, the retiree does not give out gifts. they are just the
recipient of a gift. With 75-80 people, it could be alot of $$ to give out a gift. what about a donation to the school library for books? Maybe combined with a gift basket that gets raffled off? ie to whoever sits in seat X or has something on the bottom of their chair.... or have all the names in a basket and have the animated teacher, in our case, would be the PE guy, pick out names from a hat.....
Could be a really nice basket or 2; or one for every number of years you worked there. But not for the entire group.
You could include and tell a story about what is meaningful for you in the basket.... ie....Johnny in second grade liked football (include a football), I like making jam, penmanship is critical (#2 pencils), something about cafeteria food, etc.... My favorite book is X, Ill never forget my first day,.... Which brings me to the my last day w/ support of friends / colleagues (something with a heart). You get the idea. It could be a story and could be fun and much better than a bookmark. Enjoy your special party!
Congrats on your retirement and hope you are recovering well with BP.
Best,
Barb