This year my son turns ten and I’m in that strange period of being Dad / a Yr 5 teacher. Needless to say, he’ll be getting some presents that involve solar construction this year 
For my Aussie readers I found this great ‘Thinking Toys’ website called ‘Brainy Days’ where I bought this solar construction set for us. I’ve also bought all my nephews presents from this website. I know, I know… I’m walking that fine line between Uncle Ad and nerdy teacher hehehehe
Amazon has many kits like this one Solar Car Assembly Kit but for me Brainy Days saved me a heap on postage
Ad
PS In my classrooms I have tried the general solar kit that makes a fan and other stuff, but until you make a car that rips across the floor owered by sunlight you are not really hitting the mark.