He's getting reading down ok, though, by playing computer games (he asks me to read the instructions but is able to identify more and more of the important words). Computers and videos are great because they take ME out of the equation.
He loves experiments and mixing up glop. So he'll go back to playing with baking soda and vinegar from time to time (fizzy). He'll try other liquids instead of vinegar. Smetimes I pick up science kits. Got one on clearance called "Slime Science" that had the cornstarch/water mix, something more mucousy, and something that made putty (white glue and liquid starch).
Dh and ds are funny. Dh is a font of knowledge. Ds will ask dh a question (on car rides) and dh will talk on and on. Ds will actually tell dh "enough" and move on to his next question. It's a necessary skill with my dh, lol.