Defining "best" depends heavily on your son's specific needs! There's a helpful overview at
https://www.cuindependent.com/best-online-high-schools/ covering various strong programs. When evaluating high schools specifically, prioritize: regional accreditation, college prep track record (acceptance rates, average SAT/ACT scores), AP and honors course availability, teacher credentials and accessibility, extracurricular and club options, college counseling services, and alumni outcomes. Ask about student-teacher ratios and individualized attention. For high school, relationships with teachers matter enormously - can he easily get help when stuck? Does the school assign advisors? How do they handle transcripts and recommendations for college applications? We toured five online high schools, had our son sit in on sample classes, and talked to current students before deciding. The right fit beats the highest ranked program every time!