Ohh Ooooh, call on me, call on me!
1)Can you two work on a Flower and plant based version of Yu-gi-oh? He could decide what qualities the various pants and flowers have and work out some game mechanics where 2 players could battle by dealing out homemade cards that have pictures of the species and their powers. Think Rock/Paper/Scissors squared.
2)Create his own fact books on his favorite animals or baseball teams
3) Write fantasy interviews with characters for HP. Maybe for the HP newspaper, but maybe for Sports Illustrated, or the local school newspaper, or some other offbeat venue. First brainstorm which questions would be good for various characters, then brainstorm what the answers might be.
4) Create 'apples to apples' style cards for the Hogwarth's characters and adjectives that stretch his vocabulary.
I don't know of a single boy-boy sibling pair that are that close in age that don't face the issue of the younger thinking that he is inferior. Remember that there are advantages as well - you don't have to worry about younger feeling like an alien because he's too smart, for one. Most of those 'youngers' do try harder - and that's awesome!
Love and More Love,
Grinity
