“Although scads of red are always stomach-dropping, I’m really going to learn a lot from this interaction.”

I’ve taught writing, off and on, for more than 10 years, and received plenty of feedback from students. The note I just quoted, though, was a little unusual. Its author is the first person I’ve “taught” without ever meeting. My interactions with this working adult who wants to improve her writing skills have taken place entirely via email.

Since the late 1980s, online education has steadily trickled down from universities to high schools, and now to younger students. This fall, the first virtual public school in Massachusetts opened in Greenfield, with students in grades K-8 statewide eligible to enroll. Although the opening of the Massachusetts Virtual Academy has sparked controversy, support for online schools is growing. In its 2010 annual survery, Harvard University’s Program on Education Policy and Governance found that 52 percent of the public thinks high schoolers should receive credit for courses taken over the Internet, up from 42 percent the year before.

As a former high school teacher who now teaches creative-writing and study skills, at both the university and adult ed levels. I see technology as a blessing—mostly. Once upon a time, the teaching of writing went something like this: Students would do battle with the school’s aging printers, then breathlessly hand me several crumpled pages that may or may not have all been intended for English class. A week and a dozen paper cuts later, I’d return them, covered in largely illegible handwriting.

Then I started collecting work electronically, and began to reap the benefit of other distance-learning technologies. A student could email a piece, and I’d return it with comments he could read while also creating an automatic copy for myself. I could comment on pieces far more quickly while the writing was fresh in students’ minds. Students could use a course website to peer-edit each other’s work and also access assignments when absent.

Still, until this fall, I’d always used technology as a complement to the classroom environment. Interacting with a student exclusively online has been a very different experience. My role is far narrower: I see the woman’s writing, but nothing else. Since she’s a focused adult who has spent 15-plus years in classrooms, my comments on her prose may be all she needs. She’s told me our interactions are helpful, and I’m glad. But it is hard to imagine this kind of remote interaction serving the needs of younger students, especially those who don’t yet understand what they need to learn. For me, email exchanges proved useful as a starting point with students. But it was in class and conferences that I saw them grasp why a specific sentence was made stronger by a particular change—and came to know them as people, too.

Earlier this year, Bill Gates, whose educational foundation has become a priority-setter for American schooling, called for the use of more interactive technology in classrooms. “So far technology has hardly changed formal education at all,” Gates wrote in his foundation’s annual letter. “With the escalating costs of education, an advance here would be very timely.”

Happily, Gates’s letter recommends use of the Internet as a complement to “face-to-face learning,” but his emphasis on the potential cost-savings is a little alarming. Sure, online learning may seem cheaper: You can send a 12th-grader to an online private school for about $2,000 a year, well below the $18,000 average per pupil expenditure in the Boston Public Schools in fiscal year 2009. But the reduced cost may indicate a reduced experience.

After all, online schools typically offer fewer services. Florida–based Forest Trail Academy, an Internet high school, advises prospective parents that if their child isn’t entirely self-motivated—if she or he is, in other words, a typical teenager—the parent should be prepared to play a role akin to that of an old-fashioned teacher: supervising, motivating, even tutoring. (“Having a stay-at-home parent can be a great asset,” the website advises.) Cost “savings,” then, may just be code for “costs passed onto families.”

Like so many other educational trends, online learning offers both great advantages and great potential pitfalls. It can allow teachers to better tailor lessons to individuals, allow kids to better work at their own pace, and mean no student will ever again have to squint over an English teacher’s chicken scratches. But it can’t replace human relationships—nor should we ask it to.