We have a family tradition that started because I needed one day of the week to be a no-brainer when I was planning menus. One day a couple years ago, I decided that Fridays would be pizza nights at our house. We like to make pizza together, and since not all of our kids have adventurous taste buds yet, we usually make more than one kind each time.
This night, we each made our own mini-pizzas. I gave the kids a ball of dough and they helped roll it out and loaded up their own pizza with toppings.
After dinner, clean up is quick (one of the bonuses of pizza night!) and then we either play games or hunker down in the family room to watch a movie together. This tradition started just because I was trying to simply our life and has become something everyone looks forward to each week.