The invitation was a box of Legos. I made the box out of black cardstock, then I was able to put real Legos into it.
Going with the theme of "Come Build a Birthday Party" my friend served Build-Your-Own Nacho and Taco bar and for dessert Build-Your-Own-Sundae (Carson doesn't like cake).
When the kids came through the door they guessed the number of Legos in a jar (343!). Then they assembled car kits which I purchased from ebay--old Happy Meal toys. They raced the cars a few times.
The next game was a Minute-To-Win-It type of game. The kids had to stack Legos as high as possible in one minute.
The last game was also a timed, quick moving game. Each child had two plates placed before him. One plate had a few Legos on it, the other was empty. At the "go" signal, each child had to transfer all the Legos from one plate to the other using just a straw, no hands.
The take-home bags were made by cutting out foam circles and taping them onto a plain goodie bag. Inside the bags were: 1. homemade crayons 2. Lego candy and 3. a small Lego kit. The boys were also able to take home their race car.