Hi Mia,
We are totally in the same boat! My DS6 is in a class reading big chapter books w/the older kids and has to write book reports. He hates writing. What I have been doing is having him tell me about the book, and as he tells me I write down what he is saying. Then the hard part getting him to copy what he has told me. Eventually he gets it done but not w/o complaining through it all. He would never sit there and write a report on his own. This way the words are all from him but I have to push him to write it.