In a “flipped classroom,” teachers record the lectures they’d normally give in class and students watch them at home. Then, students use time in class for activities—what in traditional classrooms is called “homework”—and to get one-on-one help from a teacher. The goal is to make better use of classroom time for dynamic, hands-on experiences.

There’s been a lot written about flipping classrooms, but here are a few points that sometimes fly under the radar:

1. The model has been around for more than a decade.

Most people had never heard of a “flipped classroom” until 2012 or 2013, when the new model received national coverage in the New York Times and on NPR and became a daily topic on education websites. But the origins actually go back to a small town in Colorado in 2004. The district was relatively rural, and high school chemistry teachers Jonathan Bergmann and Aaron Sams struggled because their students, many of whom were high school athletes, did not have enough time for homework in the evenings. Students in the rural district often spent inordinate amounts of time traveling to sports or extracurricular activities.

In 2007, after reading about new technology in a magazine, they decided to start recording their lessons using PowerPoint presentations, audio, and screen captures and asking students to watch them at home. Voila! The flipped classroom was born. (Well, after several years of tweaking and perfecting from there, that is.)

2. Kids don’t just “watch” a video.

In a recent post at Edutopia, Bergmann and Sams argued the word “watch” is too passive to capture how students interact with flipped classroom lectures—kids “watch” a TV show or movie.

“We want them to interact with the video content,” they wrote. “There is research which states that passive learning (even learning with video) doesn’t help students achieve more.”

For a low-tech solution, they suggested asking kids to pause the video and try a problem on paper. For a higher-tech option, ask them to write responses in a Google form as the video progresses.

3. You don’t have to flip your whole class.

Yes, usually when people talk about flipped classrooms they’re referring to flipping the whole class. But there are tons of resources for flipping only one lesson or one unit. The Flipped Learning Network also invites teachers to flip one lesson for one day in the fall and provides resources for teachers who are interested in giving a flipped lesson a try.

4. Teachers don’t necessarily have to record their own videos.

Along with a rise in popularity of the flipped classroom has been a flood of new tools, videos, and prerecorded lectures teachers can substitute for their own recorded lessons. For example, TED.com has a feature that lets teachers create a flipped lesson from a TED Talk. Khan Academy’s enormous library of lessons also helped popularize the movement.

5. Video will never be a replacement for good teaching.

Although there’s been plenty of positive press on the benefits of a flipped classroom, there’s also been a healthy dialogue on the pros and cons.

Lisa Nielsen, educator, author, and blogger, has written repeatedly about the need to question the merits of at-home lectures.

“I believe the most effective way to learn is to do work that’s meaningful, not to sit and watch someone else do something. This is not revolutionary,” she told the School Library Journal in 2013.

“If there’s a video that can help someone understand something, that’s great. I just don’t think that should be the be-all and end-all.”

Nielsen also pointed out that each student watches the same video, leaving little room for discovery or following their own interests.

Plus, not every kid has an internet connection or a device to watch videos on, something Bergmann and Sams have addressed with alternative strategies.

“Where I was teaching, 25 percent of kids didn’t have internet access at home,” Sams told Remake Learning in an interview in 2013, adding that he was typically able to resolve the problem by putting videos on flash drives or DVDs. “We need to provide something for the students. A laptop you can check out. It’s a problem, a hurdle, but it’s usually something that can be resolved. I don’t think it’s a deal breaker.”