The Next-Generation Classroom AV System

Our classroom AV systems are built out of the standard kit: projectors, interactive whiteboards or projector screens and staff laptops or classroom iMacs. They're all coming to the end of their lives and it's time to re-think what we want and need out of classroom AV.

The current setup has several problems.

Projectors generally stink and the ones that don't stink are unimaginably expensive. Not only do they suck but they produce a soporific fan noise, the contrast ratio is terrible, the colour reproduction is lame to start with and only goes downhill from there. The cost of replacement parts is daylight robbery. Further, unless you buy a really, really good (read: expensive) one, your classroom has to be as dark as the bottom of Jabba's Sarlacc pit to get the image visible.

Next, the interactive whiteboard. Never has so much money been spent so indiscriminately to so little effect as has been spent on interactive whiteboards across education. IWBs are pure skeuomorphism - a digital blackboard - intended to "increase the use of technology in the classroom" without changing classroom practice. We bought them, mostly, just because every other school was buying them and well the entire country can't be wrong, right? They have been a horrible waste of money. I do not have one single good thing to say about them.

Finally, the audio problem has always been difficult. Plug a laptop into this system of audio and video and power cables and you end up looking like you're teaching from inside a life support system. We have never found a good, cost-effective solution for broadcasting the audio. Not to say that one doesn't exist - we just haven't found one we really like.

So, with all of that in the background, I set out to design a new classroom AV system that took advantage of the fact that we have iPads in everyone's hands. I decided to start with what the teachers wanted, so I asked them. The only teacher still using the interactive whiteboard for more than a projection surface was our maths teacher who found the ability to annotate on top of prepared content valuable. Everyone else had basically given up on the device.

So I spoke to the teachers and asked what they were using AV for in their classroom. The answers that came back were as follows:

  • To display Keynote presentations - either their own or ones the pupils had produced
  • To show a web page
  • To show photos
  • To show a video to the class
  • And, of course, the one we've wanted for a year - to demonstrate an iPad app.

Now, at the same time as we are looking into upgrading the AV, our old iMac desktops (iMac4,1, the first-generation Intel iMacs) are nearing the end of their lives. They've done sterling service since 2006 but they're not going to last much longer. Replacement is definitely on the horizon.

Consider the cost of refreshing our current setup with today's equivalents:

  • Base-model 21.5" iMac: £950
  • Projector: £390 (average)
  • Smart board (64" diagonal): £1256(!)

That's a total of £2596 to refresh an AV system that has no real solution for the A-part. That price is held down by specifying an iMac rather than the MacBook Pro that most teachers would want. I think we can do better, where "better" is defined as: cheaper, more flexible, neater, more reliable and enabling new classroom practice around the 1:1 iPads.

So I came up with the following parts list:

  • Sony Bravia KDL40EX401U 40" TV: £399
  • Base model Mac Mini w/4GB RAM: £650
  • Apple Bluetooth Keyboard & Mouse: £105
  • AppleTV: £100

That's £1254, or, one SmartBoard and a cup of coffee. Here's what it looks like:

AV System: Mac Mini

Why is this system good? Well, I'll report back after some use, but here are my ideas:

There's a computer in there. We still need this for syncing iPads at the moment and staff will still want to present full-power Keynote presentations from a Mac. Keynote/iOS is coming along nicely but I don't think it's quite there yet. With a BlueTooth keyboard and mouse, we can control the Mac mini from anywhere in the classroom. Better than that, though, we can open up the Mac mini to VNC control and deploy a VNC client on our iPads to allow anyone to control the classroom computer from their iPad. I personally like iTeleport but there are many, many options for this.

The Sony TV has 4xHDMI input and one VGA. Two are given over to the Mac mini and the AppleTV and we currently have the iPad VGA adapter on the VGA port. As and when we get iPad 2 and the HDMI adapter, this system will accept that on another HDMI port, so we have some spare capacity.

You can have any student take control of the AppleTV from their iPad over AirPlay to share videos or photos. I personally use a lot of YouTube videos to teach automated systems in Computing. When pupils are researching content, they can share what they've found wirelessly. Secondly, you can send photos to AppleTV from the Photos app. Our Art teacher, Jenny Oakley, is desperate to have this in her classroom to allow pupils to present their artworks on a large display.

AirPlay is just getting started. iOS 4.3 just opened up the APIs to third party developers so we're anticipating that more software will acquire the capability to share content over AirPlay. Looking at you, iPlayer, Sky News, et al.

This solution solves the "audio problem" because the audio is routed through the TV for both the Mac mini and the AppleTV, both of which are connected over HDMI. It's also a dramatically neater solution with fewer trailing cables.

Another great advantage of this system is that LCD TVs are much, much more durable than projectors. Typical projectors are rated for 1000-2000 hours of operation - and that's operation at all, not high-quality, good-colour operation. I've seen numbers up to 100,000 hours quoted for LCD TVs. Even if 100k hours is an overstatement by one order of magnitude, that's still a huge win over projectors.

What do we lose over the old system? Not much. We lose the interactive whiteboard capability that we mostly don't like and don't use. We save a ton of money and get a more flexible, longer lasting, neater AV system that opens up a new range of capabilities.