I have my boys take the notes from their graphic organizers and transfer them to an outline. It really helps to put all the bits of information in a usable order.
Step two of the writing process is the rough draft.
I have NumberOne take each point on his outline and write a sentence.
I think we make the process a bit more complicated and step-y than normal, but with my boys it helps. It's like when I have a short list of things I want them to do. "Carry your socks and shoes to your room, bring back the trash from the bathroom and unload the dishwasher." If I give them the list all at once, here's what usually happens. They carry one sock and shoe into the bathroom and put the trash can in the middle of the kitchen, then forget the dishes altogether. So I have to tell them one thing at a time. "Take your shoes and socks to your room. "Once they are down the hall, "Bring the bathroom trash to the kitchen and dump it." Once in the kitchen, "While you're in there unload the dishwasher for me."
The point is that the sentences at this point may not appear to "go together." That's OK. The next step is proofreading for capitalization, spelling and punctuation.