@MrsPramm - Getting any children to the point where they are comfortable enough to take risks seems to be the biggest hurdle I come across when teaching writing (or anything, really).
We did a bit of research on this at my school last year and I found it helped a lot to group the kids or pair them up with each other then ask them to get their buddy (or group) to check their work before the teacher saw it.
Before I had them do this, I would be called from student to student for the entire class and half of them would be waiting for my input because they didn't want to continue without reassurance.
After they started this peer-checking, they got the reassurance they needed from each other and didn't lean on the teacher so much, which was good for everyone. An added benefit was that, by helping each other, they increased in confidence because they felt like they were being considered an expert.