So long as he seems to be enjoying himself I wouldn't care what his rating was. But if he wasn't at least 1500 in six months I recommend a weekend with no food under the stairs for letting you down so dramatically.
How fast can a 1st grader improve his / her rating
This year my son is trying to get to 1,300 by end of the year. It will take some effort as the competition is getting much tougher in the 1,000-1,400 sections and you don't have many easy games. He is also usually one oomph a handful of second graders playing much older kids. But I support his goal as it is potentially attainable and I make it clear we are proud regardless and he should try to focus on enjoyment and improvement and that the ratings will naturally follow in time. If he had set a goal like 1,400 or 1,500 for this year would have talkEd him down as that is simply not reasonable for my son.
Assume USCF 850 now (after 7 tournaments) -- where could he be in 6 months with a reasonable but not crazy amount of practice? 1000? 1100? 1200? Curious to hear opinions of other chess parents.