Post-secondary online learning is more developed than K-12
Evidence that online learning is more developed at the post-secondary level than at the K-12 level includes:
A higher percentage of college students than K-12 students take all of their courses online.
A higher percentage of college students take at least one course online.
Federal data systems at the post-secondary level are better at distinguishing online courses and online schools/programs from physical schools/courses.
15.4% of all post-secondary students were “enrolled exclusively in distance education courses.”
17.6% of students were “enrolled in some, but not all, distance education courses.“
Together, that means that about one-third of all college students were taking at least one online course.
The data show that the percentage of students taking all of their courses online is significantly higher in private for-profit institutions than in public institutions. However, even if we look at just the public institutions, the percentages are still much higher than in K-12 schools.
These large data sets are supported by anecdotes from individual institutions as well. For example, Rutgers Report Views Online Classes As the Future explains that “Ten years ago, 1,234 were taking online college courses at Rutgers University. Last year, in the fall semester of 2017, that number reached 23,042, according to university figures… ‘If we're going to make Rutgers as accessible and affordable as we can, we've got [to] embrace online portals,’ university President Robert Barchi told the board.”
The same article notes concerns that are similar to some issues at the K-12 level: “Among the challenges facing this form for education is the concern of faculty, Novak said in his report. Less than one-third of all chief academic officers at colleges university, 29.1 percent, believe their faculty accepts the value and legitimacy of online educational programs.”
Comparison to and implications for K-12 education
The same numbers aren’t easily available for K-12 schools, but based on the best estimates, the K-12 numbers are lower than the post-secondary numbers.
Probably about 1-2% of K-12 students are taking all of their courses online. We have a reasonably good estimate on this and will be publishing a white paper on it in the coming months.
The number of K-12 students taking at least one course online is much harder to determine. Across all K-12 grade levels, the percentage is definitely much less than the post-secondary percentage. The percentage among high school students is almost certainly less as well, but much closer. We hope to dig into these numbers further in 2019.
I don’t mean to suggest that K-12 schools should match post-secondary institutions in all the percentage of students taking online courses. High school students are of course different than college students, and that difference increases in middle school and elementary school students.
However, the post-secondary data suggest two main findings.
First, the extent to which colleges are using online courses suggests that thoughtful post-secondary educators believe that online courses can be a successful mode of instruction for a wide range of students.
Second, the availability of online post-secondary courses suggests that there is value in a high school student taking one or more online courses simply to be better equipped for post-secondary education.
 Ginder, S.A., Kelly-Reid, J.E., and Mann, F.B. (2018). Enrollment and Employees in Postsecondary Institutions, Fall 2017; and Financial Statistics and Academic Libraries, Fiscal Year 2017: First Look (Preliminary Data) (NCES 2019-021). U.S. Department of Education. Washington, DC: National Center for Education Statistics