I just did a "60th" B-day Party for my mom. I set up 6 tables for people to sit at and the centerpiece of each table was "stuff" from that decade. Most of it was my mom's but some I had.
For example the "50's table" had an old quilt my mom had as a child for the table cloth- some of her old dolls she played with, a few photos of her as a baby/toddler/child, then a few icon things- an old Elvis luch box, fuzzy dice, a 1950's classic toy car, etc.
The "60's Table" was a tye-dye table cloth, then her letter from Highschool, her old year book, some old articles she had about John Glenn and other space stuff. Also a few photos of her in her cheerleading outfit, her and my dad dating, etc.
We did a table for each decade and then just used solid colored napkins and plates. It did take some time to put everything together- mostly for her to dig her old stuff out- but the guests really enjoyed looking at all her old stuff and all the pictures. I also did some fresh flowers from Costco on each table.
I also strung some clothesline against a wall in my living room and used clothespins for people to hang up "Memories" that they had written about my mom. Lots of people got into this and it was neat to read everyones favorite stories or well-wishes. Very cheap!
HTH!