What do most studies show is the number one way to increase your childrens intelligence and academic ability in their formative years? Read to them. Anything, it actually makes almost no difference what you read. I read the girl with the dragon tattoo to my 6 month old and carried on with the next two books whilst he got to about 15 months. Had to change material then as I didn't want his first word to be something like "rape".
What is then shown to be the main thing to improve academic performance from 6 to 18? Attendance. But reading is second!!
Reading simply does make you smarter (again the subject material makes startlingly little difference, don't think I'd ever denigrate anything anyone was reading it's surely a better use of their time than watching 99% of things on TV) and I say this as someone who used to read a lot but barely does nowadays. Kudos to those who make the time though. Mostly nowadays I just carry a book around with me and read a bit as I want my children to see me reading and I want my pupils to see me reading as it's going to make them more likely to and it's the best thing they could be doing with their spare time. Currently the bluff is very much working with my son, score!