Which grade should an American child be in who will be 7 in November 2009?

This depends on the "cut-off date" in whichever state the child lives in. That means that when a child starts kindergarten (the first year of school), they must be 5 years old by that date. In many states, it is sometime in September, so kids with November birthdays are among some of the oldest in their grade. In that case, a 6 year old turning 7 in November would be in 1st grade. But if they live in a state with a later cut-off (some states have it at as late as December) and his/her birthday is before that date, then he/she would be in 2nd grade, and would be among some of the youngest kids in his/her grade.