My kid is six and can read 100+ page kids books in about an hour (she doesn't do this super often though). It wasn't too hard to teach her to get there either,

My kid is six and can read 100+ page kids books in about an hour (she doesn't do this super often though). It wasn't too hard to teach her to get there either, but repetition is key. We started when she was 4 by reciting all the sounds each letter could do each night. It used to take us almost an hour to get to Z, but eventually she got it down fast. I tried to make it as fun as possible. Then we would do two to three letter words and have her figure out the words by using those sounds (sometimes trying various combinations until something made sense). We did that a few nights each week for a few months while she was playing. You can't force it, but I could usually get a few words in here and there. Then we started very simple sentences with the various Bob, Learning Dynamics...etc books. This was a big shift, but became easy soon enough. After she got through ~50 of those short little books, we moved on to the beginning chapter books when she was almost 6. She could earn certain privileges like TV if she reads a book. I kept reading to her (story time) as well each night. She's in kindergarten and reads like a champ now. Her school work goes over additional phonics stuff which is good to fill in any gaps she got from my very non-academic methods (I never really learned the rules as a kid...I just liked reading and I guess picked things up organically). It's pretty cool that she can pretty much just read anything now that isn't a very unusual word you just have to know. She sometimes guesses at words though that are wrong, so we're working on slowing down a little bit. It's a balancing act though. You don't want to make it such a chore that they don't want to read later, but I just don't think the math and reading is very good at school so far, so I'm trying to supplement. Spending a few hours on reading and math outside of school each week seems to eat up a small amount of free time, but lead to big successes.