I think the editorial doesn't make clear exactly what "online courses" mean. There are two ways to interpret the phrase: 1) Normal high school students go to

I think the editorial doesn't make clear exactly what "online courses" mean. There are two ways to interpret the phrase: 1) Normal high school students go to community and technical colleges and possibly take online classes. In that case, you are correct 2) In washington state, you can actually take online classes in high school and even k-8 (k12.com) and my understanding is that there have been studies on k12 students and their performance in community and technical colleges as a function of whether they went to a physical or virtual elementary and high school. I am guessing they are referring to the latter (where other studies -- take a quick gander at google -- do draw the conclusions that the article refers to as "well known") Unfortunately I couldn't find the study that the article is explicitly referencing.