Penn Foster High School advertises that they are available to students of any age. https://www.pennfoster.edu/high-school/admissions/audiences
If dual enrollment interests you, Bluefield College offers a very affordable program... http://www.bluefield.edu/admissions-aid/on-campus-admissions/dual-enrollment/
Thank you! I am homeschooling my kids. While I mainly focus on common cores: language arts, mathematics, sciences, and social studies. Based on my current schedule, they should be able to start the high school curriculum in two years. Although it is okay not to have a high school diploma, I ensure they are not missing it. All the accredited online high school I looked up requires at least 13 years old.
Actually Penn Foster High School requires at least 13 years old. " Q. Can adults enroll in online high school with Penn Foster? A. Penn Foster welcomes students of all ages, including adult learners. Enrolling in our high school program is open to anyone 13 years or older who has completed the 8th grade. We know how challenging it can be to earn your diploma as an adult learner so we do our best to make it as easy as possible for you with our online and self-paced learning platform."
How young are your kids? The programs online are geared for several age groups: K-12 (under 18), College Prep or upgrading for Adults (over 18). Depending on their age, I would use any free yet well made study materials online for K-7, and if they're gr 8-12, use materials such as Khan Academy/Onlinedegree.com and Saylor.org courses so they can get "dual credit". I like to advise people to accelerate and compact their educational goals and learning time by using the summers. Technically, one can homeschool and excel from K-12 and be done in a couple of years faster than the normal traditional method.
If I had a kid who was, let's say, 10 years old and they wanted to be in high school and I wanted them to be in high school and there was some concrete evidence that the kid was capable of doing good work at that level then I would put together a very nice package of information - application forms, transcripts, cover letter, essay from the kid about "Why I want to be in high school" or something like that, and I would present that package to the online high school of my choice and I would force them to turn the kid down. I'll bet that if the kid really belonged in high school then they would see that and they would bend their own admission rules and let the kid in. That's what I would do, force the issue.