I'm glad he had the time to share that with us. This makes me want to take my old k'nex set out of the closet for the my son. He's on megablocks right now (the type that can't be swallowed). Thanks for helping me think about him.
Your are a wonderful father sir. I had so much fun playing with my set as a kid. Now I'm playing with molecules and math. I'm partial to legos, k'nex and the like, so you have an unfair advantage. The upside down K'Nex Roller Coaster box waiting in the closet for my son.
When I was a kid, my brother and I built "lego city" which took up about roughly half the space in our bedroom. I have old pictures this that I will post here after I have hundreds of polaroids from the 1980's and 1990's scanned and turned into digital photos.