Where is the line between Helicopter Parent and Helpful Parent

The new school year has started and our Daughter is now a Sophomore in High-School which means it's time to start to start paying serious attention to her graduation and college. We have always considered ourselves to be involved parents while not being "Helicopter Parents" but my wife has seemed to step up her involvement while I think we should actually be stepping back and letting her make more of her own decisions, which means more mistakes.

I'm having a hard time figuring out where the line is. An example of this happened even before the new school year started. At the end of the last school year everyone in the AP Lit and AP History were given assignments.

For Lit it was two book reports, for History it was study material for a quiz that would be given on the first day of school. My wife didn't really say anything to my daughter until about 3 weeks before school started. I asked her about it twice and I was content to let her decide to do it or not and face the consequences of her actions. My wife agreed somewhat but as the new school year got closer and closer she couldn't stop herself and started really getting on my daughter about it. She had done very little with one week left and then my wife went into full intervention mode and made my daughter sit there and do it.

I told her to let my daughter decide on her own but she was in that mode now and there wasn't any stopping her. So, she got the work done reported for school and..... Yep. My daughter was the only one who had done the reports and the History test was postponed.

Now, you would probably think I put this in the "win" column for Dad but I don't. All the other students will get points taken off their grade no matter how well their report is when they turn it in. My daughter will start off the school year with a high grade in an AP class and she saw that the time she put in to get the report done was worth it.

I think my daughter knew that the other kids weren't going to turn their assignments in but she knew she couldn't say that to us because then even Dad would've gotten in the mode and had her working day and night to have the best reports seen to mankind. She knows that saying she should or shouldn't do something because other kids are doing it is a felony offense.

There are going to be more and more of these types of issues for the next two years. I want my daughter to do more and more on her own which entails making and learning from mistakes, but I also don't want her to make mistakes that will hurt her to badly. Any advice is greatly appreciated.