My DS has just started at secondary school (selective grammar). He is great at Maths and problem solving, less so at comprehension. I've noticed with quite alot of his home that there is a comprehension type element to it - even for science etc, the task will be to, say, summarise the article about the most dangerous plants etc.
We read every most night together, he occasionally will read on his own (not very often despite buying books for him / trips to the library etc).
Anything else that may help him?