By fourth grade, your child should be starting to read on their own, which means it becomes all the more important for them to fall in love with what with they're reading!  This is also the age range that teachers start to help students develop their ability for in-depth analysis and other reading comprehension strategies.  As parents, the best thing is for your child to fall in love with reading on their own time-which means, excellent books: 

Some other things you can do to help your child develop reading skills include asking them about their reading, reading with them, or helping them find books that they love if the recommendations above aren't their style!