The hit song from the 90s, the future's so bright I gotta wear shades, would be a fun inspiration for a Teacher party.
Go retro and have guests dress in 80s and 90s attire and of course they should wear their sunglasses.
Use bright colors for the decor like hot pink, lime green and purple. If you have the money, order some inexpensive colorful sunglasses from orientaltrading. Use them to decorate and encourage guests to wear them too.
