Best Add-on for the Sparkfun Inventors Kit

My nephew is getting the Sparkfun Kit RTL-11236 for his birthday and I wanted to know what a good add-on for it would be. He is 11 years old, started with the Lego Mindstorms product a while ago and last year joined a robotics team, so I expect him to be pretty comfortable with most of the concepts. I’ve found several ideas looking across the forums and store, such as the LCD Add-On as well as a couple of suggested arduino programming books.

Since I am not as familiar with these things, is there any must have add-ons or tools that would go with the kit best?

Thanks.

JB

It really depends on what interests him. Does he like making things move, or does he like reading sensors (LCD), or music. I am guessing since he joined a robotics team that he likes to make things move. Which would say maybe a robot chassis with motors and servos.

Maybe something like https://www.sparkfun.com/products/10336