Imo, the way to approach this to return to school is to do none if the assigned online work. This would be difficult to do and 180 degrees from how I was raised and approach things. However, it is very likely that grades will be pass/fail and I've yet to encounter a public school that fails very many kids regardless of what they do or don't do. Not doing online assignments will reflect poorly on the teacher/school as they try to convince everyone that they are providing a quality education. The more one can convince to do this, the more pressure is put on the school.
If worried about eligibility next year, most states I'm familiar with waived the requirements for this fall and all were eligible.
Worried about standardized test scores?- they're becoming a thing of the past as well, as many colleges offer admission without ACT or SAT.
Schools are humiliated with low graduation, low attendance, and high dropout rates. Humiliate them and you may have better options.