I've just signed up for my first class at "Peer 2 Peer University," which isn't a university at all but what it calls a "grassroots open education project" matching volunteer instructors with learners around the world. All classes are free.

I'll find out how well a volunteer-run Web class works in the upcoming weeks. Meanwhile, though, I'm grateful for the chance to improve my GIS skills, which I've been trying to burnish ad-hoc. (The only other relevant instruction I found so far involved a week-long out-of-town workshop, which wasn't in the cards). Based on the writeup of my course instructor -- a Carnegie Mellon student who spent last summer teaching in rural Uganda, -- this seemed worth a try.

I found it interesting -- and a good sign -- that instructors vet us would-be students, probably to make sure we're serious. After all, it's all too easy to apply for a class that's free and then fizzle out, and openings are limited. (Students needed to send in some HTML/CSS code before being admitted to class.)

The next round of P2PU classes begin January 26.

The Mozilla Foundation says it's working with P2PU to offer the "School of Webcraft, developer training that's free, open and globally accessible," but there are other P2PU classes available as well.

If volunteer schooling isn't your cup of tea, yet you a) want to learn a new skill but b) can't commit to getting to a classroom regularly, here are a couple of other Web-based instruction sites I've used recently:

O'Reilly School of Technology

I'm finishing up my third class with this partnership between the O'Reilly tech publisher and University of Illinois. The school offers certificates in skills like programming, database administration and Linux/Unix administration, although classes are offered individually as well.

I can't vouch for how much sway this training holds with would-be employers, since I've yet to apply for an IT job. But I can say that the skills I've picked up have helped me solve real-world problems, such as automating drudge work with scripting and crafting database queries using SQL.

You take these classes at your own pace -- a mixed blessing for those of us who need flexibility but also tend to perform better on deadline than "whenever you finish." Classes are text-only (no video or screencasts), but also include a lab environment/development sandbox where you can practice coding without installing software on your own system. After each lesson, there are quizzes and/or coding assignments to hand in to demonstrate you've absorbed what was explained. Assignments are graded pass/fail.

The course mentor who does your grading is also available to answer questions by e-mail. I've found this ranges from "won't help unless the question is directly related to the syllabus" to "way above-and-beyond helpful."

Classes come with a free e-book related to the subject of your course, although the book isn't a textbook to use in conjunction with your instruction.

The courses are definitely useful, even if they occasionally move too slowly at some times and too quickly at others for my tastes. I do end up with new or improved skills, which is of course the point.

Courses are usually around $300 or $400, although there are occasional sales such as this month's 25% off.

Advantages: Access to an instructor so you can get questions answered, graded assignments make it more likely you'll do needed work to absorb what was taught, certificate series allow you to build on what you've learned in other courses.

Disadvantages: Interaction with instructors limited to e-mail, no interaction at all with other students, fairly pricey for static text classes.

Lynda.com

We've got access to Lynda.com at work, and it's a nice resource. If your employer isn't already footing the bill for a group account, you can get an individual account for a reasonable $25/month (no minimum sign-up time) for access to all available classes; $37.50/month lets you download course-related working files as well. Lynda offers Web-based video training on a wide range of subjects, such as how to use software like Photoshop to learning a language such as Python or PHP.

I've found this pretty useful for learning specific applications such as the Photoshop Elements Premiere video editor and Adobe Lightroom, but less so for programming skills such as PHP -- but that may just be my own personal learning style. These are also learn at your own pace, and since the video classes are broken into small segments, you can skip around if you choose.

Advantages: Affordable, wide range of subjects.

Disadvantages: No instructors so you're on your own to answer questions, no lab work or assignments to make sure you've understood what's been taught, pacing of videos may not be to every student's liking.

Ed2go

It's been a number of years since I've taken a class here, so I can't give concrete advantages and disadvantages for how its structured today. But what I liked about Ed2go when I used it was having access both to instructors and a discussion area where I could see what questions other students were asking.

These courses have structured start and end times, but new sessions usually start each month so it's reasonably flexible. Ed2go's Computers and Technology offerings include programming (Java, Visual Basic, PHP, Perl, MySQL, Python and Ruby, among others) and there are areas for security, database management and certification prep. You actually take the class via a partner school or organization, not directly from the company.

Anyplace you've used that you want to add? Have experience with one of the places I mentioned? Drop me a line or leave a comment below.

Sharon Machlis is online managing editor at Computerworld . Her e-mail address is smachlis@computerworld.com. You can follow her on Twitter @sharon000, on Facebook or by subscribing to her RSS feeds:

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This story, "Free/Low-Cost Tech Classes" was originally published by Computerworld .