When the teacher decides if the child can go up a level in reading they consider the child comprehension as well as the reading skills.
But teacher do you consider if the individual child is chatty or does not like to speak too much? I mean at the age of 5-6 probably girls are chattier than boys, or one child chattier than the other. So if you ask a child after read the book what do you think what will happen after the end he or she can have a 5 mins chat and if you ask another child he or she will tell you only a sentence but just because he or she does not like to chat that much. Or if you ask what do you think about the character in the book. Or if you ask what happened in the book. One child will tell you a story for 10 mins and the other child will tell you the main event in 4-5 sentences. But I think these differences do not mean that the first child comprehension is better than the second child, just mean the first child likes to chat a lot.
What I mean there are children in the class who do not volunteer to speak up, but if the teacher asks them they always know the correct answer just these children like to listen and they think twice before they say something. Or when you ask who knows the correct answer they do not put their hands up but if you ask them they do know the correct answer.
How do you deal with these in the classroom? Do you think about this when you level their work in any subject?