Mom... I'm Mexican!!!

Brighton came home from school last week really excited because they were assigned to do a heritage project.

Here is a part of a fun conversation we had.
Bright: MOM!! MOM!! (as he runs in the front door.) I'M MEXICAN!!
Me: What?
Bright: I AM MEXICAN!!!
Me: Ummm, ok, yes, you are Latin American.
Bright: Mom, that means Mexican. And my mommy Annette is Mexican.
ME: Yes, you're right. Are you so excited because you are Mexican? (Choosing to skip the lesson on parts of South America until I remember to look up where exactly mommy Annette is from. And choosing instead to find out why he is so excited about this fact right this minute, when he has always known his nationality.)
Bright: We have to do a report on our culture, and my culture is Mexican.
Me: It is? (Racking my brain to think what in my home is giving him the feeling of a "Mexican Culture")
Bright: Well, my Mexican family eats a lot of corn and tortilla's.
Me: Well, you love tortilla's, but you won't eat corn.
Bright: Now I do like corn. I like it because I am Mexican.
Me: Great! Tomorrow at the beach party you can eat lots of corn and tortilla's!
Bright: AWESOME!!! I LOVE BEING MEXICAN!
So we are very open about our lives, struggles, achievements, special needs, adoption stories, etc. We just talk about it all very openly and on a basic level. But now I am thinking... It is definitely time to start doing a lot more to celebrate the diversity in my little family. We have a lot of ethnic representation in our home, but we don't really have much of each person's individual "culture" being taught or celebrated throughout the year. We definitely teach a lot about our family's pioneer heritage, and we constantly talk our our eternal family going forth. But I really want my kids to know, understand and embrace their backgrounds, especially that of their birth mommies. It's kind of funny, because my Brighton is blond hair, blue/grey eyed. He looks nothing like his ethnicity, but he is FASCINATED by it!!

So, this is where I need help.
#1, Does anyone know of any special ways to celebrate being Latin/Egyptian/African American?
Any special occasions, celebrations, stories, foods, etc. Anything to honor or celebrate a "culture".

#2, We celebrate our adoption day, and this is where I want to start focusing in on each child's special culture. Any adoption day ideas from any of you out there?

Let me know!
Thanks all