The following link lists about 25, not sure if they all offer degrees. Some are affiliated with existing private schools, and others with universities (Both Texas Tech Uni K-12 and UTHS teach the standard curriculum for the State of Texas.)

https://www.bestcollegereviews.org/top/online-high-schools/

There is also a range of how much classroom interaction they require (some have a lot, others none) so picking one depends on what the student prefers for their learning environment.