This is something I have been thinking about for a long time. Now I know all of the talent is basically equal across the board based on level of play but lets look at what these coaches are teaching and how it all translates upwards.
Pop Warner coaches have to coach boys and girls, they can't cut anyone, and everyone has to play so you can't stick the fat kid on the bench all year. These coaches are responsible for teaching the kids how to run, catch, tackle, play within a scheme, and keep them engaged in the sport. Most NFL players have played in this league when they were youth. Compensatin = volunteer
H.S football coaches are broken into two catagories (public & private schools), public H.S have a no cut policy and the kid has to come from a regional area to attend the school. These coaches don't have to play all of thier kids but they may have to coach kids that have never played football before so things like snapping the football and recieving the snap from the center can be an every day drill. Compensation = $400 per month stipend
Private H.S is a different story, they do have a cut policy and they can recruit kids from everywhere. These coaches coach at a very high level however they don't have to teach a kid how to run when they can simply recruit a kid that can run. these coaches are usually next in line for a college job. Compensation = 5-6 k per month.
College coaches are almost at the same level as the NFL because they can recruit talent and offer scholarships. The players come in from H.S programs that have prepared them to an exstent, and they have skills on arrival. These kids will need to be coached in some fundamental areas but it is the scheme that matters (see tebow). Compensation = 2-5 million per year
NFL Coaches are the most recognized and get the most credit when athletes perform well, however ALL athletes that enter the NFL come with the tools to succeed (fast, strong, understand the game) to an extent. NFL coaches do not spend much time in tackling drills because players already know how to tackle. The focus once again is scheme. compensation = 2 - 8 million per year
With all of this said, the real difference is the money that each league brings in. When is comes to coaching the Pop Warner coach starts with the rawest players so they will need to conduct the most basic practices, wich may translate to these coaches contributing the most to the NFL in the long run yet these coaches get no compensation. each of the next few levels should tend to get easier and easier since the player is slightly more polished at every level. with that said, which of these coaches tend to have the most impact on the player and which would you say is the better football coach when you look at player developement?