For math, at least, the solution is pretty simple: give them the book, and let them work through it at their own pace. Hopefully the teachers can keep up with the grading...
We used the Saxon math program when I was in elementary/middle school, and the repetition was key there. I could get away with teaching myself, because I'd be seeing the same classes of problems over, and over, and over, long after I finished up the chapter introducing them. Unfortunately, after 7th grade, and burning through the Algebra 1 book, the district switched curriculums, and I didn't learn anything new until I took discrete math in college.
As someone to whom that solution was "applied", it's crap. Most teachers don't know enough of the material to answer questions, so you lose the guidance of experts, and since you're no longer working with peers, you lose the social aspect as well.
Well, it's better than the usual alternatives, in my experience. If your teachers are incompetent, they won't be able to help you one way or the other, so it's best if they just get out of the way.
As for the "social aspect", you rarely actually get to work with peers, and instead are coerced into doing the teacher's job for them. It was incredibly frustrating to drag along with people who just didn't have the brainpower to deal with the material.
I hated group work in school. It is incredibly frustrating to be forced to work with people who are not pulling their own weight, whether because they don't want to or just can't. Nonetheless, this is an important thing to learn to deal with. Frustration is part of life. So is dealing with both struggling and apathetic people.
I hated it too. Inevitably groups of 4-6 would devolve into groups of 2 who did all the work. I had one group in undergrad where all 4 people were rock solid, and that was enough to convince me that the Netflix high-concentration of talent approach has merit. [0]
From the other perspective, I was the slacker of the group, and never did any group work. I was socially anxious, and no amount of pushing me into group work made me any better at it. (sorry to you, and all the groups that I slacked on!)
> If your teachers are incompetent, they won't be able to help you one way or the other, so it's best if they just get out of the way.
Might be worth considering the effects of changing teacher demographics. For a variety of reasons the public employee unions have been eliminated, and a side effect of that is the old salary model had very low pay for the first years of teaching (like $20K) vs very high pay after 20 years in (like $80K) averaging out to a decent living, in the end. But if higher ed profits the more teachers they produce, such that they graduate 20K for 10K of job openings or whatever, plus the teachers union is toothless if not gone, that means all the teachers at my kid's middle school are under 30 and make less than $25K/yr. And this in a "good district", in fact academic award winning (the kids culture and genetics obviously matter a lot more than teacher salaries WRT outcomes). "When I was a kid" teachers were an interesting cross section of humanity from old to young, but now 95% of them are under 30. The district likes to brag about the teachers so we get a list of diplomas from the better universities (remember higher ed graduates twice as many diplomas as there are jobs, so the only people getting jobs are above median...) the side effect is that the average BS degree in Ed at my kids school was awarded around 2010 or so. The job title of an experienced teacher is "realtor" or "waitress" or honestly I donno but I assure you there are no experienced teachers employed by school districts anymore.
So the point of this is you can't handwave away demographic change... My Algebra II teacher was maybe 50 and knew her stuff after teaching it a few decades, ditto my high school calculus teacher who must have been 60. I had a parental-age economics teacher who was very influential, ditto an influential parental age history teacher and a grandfatherly government/social studies teacher. But those days are over and the financial savings of only hiring kids to teach kids are obvious BUT its also obvious that almost nobody in the building has more than maybe 5 years experience teaching. Saving money is cool, but it results in the blind leading the blind. You NEED a curricula and overall plan that assumes all teachers are inexperienced and more or less incompetent because for financial / political reasons that's what we have today to save money.
The job title of an experienced teacher is "realtor" or "waitress" or honestly I donno
In the DC region, I know 4-5 former teachers who moved into corporate training of one flavor or another. Usually internal positions (not consulting), so low travel, reasonably stable, with reasonably high degree of knowledge/skill transfer from teaching kids.
This is very important. There are lots of differences between countries with outstanding K-12 achievement. Some have lots of study, some have cram schools, some don't teach reading until 7, some have unions, others don't. One commonality: only the best students become teachers.
What worked best for me, given my (public) school's limited resources, was being bumped up a grade for math. I knew some of the students anyway, the teacher knew more about the subject area and could answer my questions, and the material kept me challenged.
We used the Saxon math program when I was in elementary/middle school, and the repetition was key there. I could get away with teaching myself, because I'd be seeing the same classes of problems over, and over, and over, long after I finished up the chapter introducing them. Unfortunately, after 7th grade, and burning through the Algebra 1 book, the district switched curriculums, and I didn't learn anything new until I took discrete math in college.