This is not a very sophisticated subject. I have a 7 year old cousin who is so bright and interested in engineering (He goes to an elementary school that focuses on science). We had gone to the USF science festival the other month and when we got to the Robotics section, he was mesmerized.
Being 23 now, I look back and wish I pushed myself recreationally in sciences. From your experience, do you have any recommendations on something that I could get him for Christmas that encourages this interest and also develops necessary skills and concept for him to "run with it".