Wade and I celebrated his 30th Birthday (see here) by attending a Monster Truck Show. We had a great time and thought this year Alex might be old enough to enjoy it. (Thankfully Wade remembered how loud it was and brought us all earphones.) Alex was mesmerized. I thought at first he was scared, or uninterested, but he assured us he was having a great time.
I really knew Alex had enjoyed it when we got home and he wanted to play Monster Trucks.