When I teach in a classroom, I use a computer projector to show students things on my laptop. (Remember overhead projectors? Those days seem so long ago.)
Most teachers only know how to mirror their computer screens onto the projector so students can see on the big screen whatever the teacher can see on their computer screen. But you can do more.
You don’t have to show students everything on your computer screen when you are using a computer projector. In fact, you can show different content on your computer projector.
I have my computer set up with an extended display so it’s like having two connected computer screens side-by-side. If I drag my mouse far enough to the side on one screen, it’ll jump over to my second screen.
It takes a little bit of time to get used to, and sometimes, it can be hard to find the mouse, but I like having the extra screen real estate.
Using an extended desktop means that I can work on things and get applications ready on my computer screen before showing it to students on the (second) screen which is projected. It means I can quickly switch from a PowerPoint presentation to a Google doc to a YouTube video to another computer program just by clicking and dragging.
It also means that I can show instructions to the students on the computer projector, but open up a confidential email or student file on my private computer screen.
How to display a separate screen on your computer projector
On a Windows machine, usually you just right-click on the desktop and you’ll have an option to change the display settings. If your projector is plugged in, you can set up your computer so that instead of the second projector screen duplicating what’s on your desktop, you can have it extend as a second screen.
I actually go one step further. I’ve brought in a second monitor that’s connected to the projector (not my computer.) This way, I get a second extended desktop screen that is projected to my students, but I can see what’s on my projector because it’s duplicated on my second monitor on my desk.
Now, I don’t have to crank my neck when I’m typing something on the data projector screen that students can see.
I use Microsoft PowerPoint to set up most of my lessons. I like PowerPoint because I can have it running on my computer screen and present the slideshow on the second screen (projector.)
Example of a computer projector showing different content to students
Here’s a screen shot so you can see powerpoint is running on my computer screen (left side) and the students see the slideshow on the computer projector (right side of screen shot.)
I also like how with Microsoft PowerPoint, I can change the slides on my computer screen and the students can watch the slideshow change in real time on the second projector screen.
I wanted to use Google presentation, but unfortunately it doesn’t have an extended desktop mode. Sure, you could open up a web browser and display that to the students, but any changes you make in a separate web browser on your laptop screen won’t show up to your students until you refresh the browser that they can see on the second projector screen.
The big downside with Microsoft PowerPoint, however, is that I’m not currently using SkyDrive to share my presentations with my students on my class website. (I use Google Apps.) My work computer currently uses Windows XP and a SkyDrive desktop app isn’t supported on XP. This means that I have to manually upload my presentation to SkyDrive after every lesson and then embed it separately onto my class website.