But none of you, including teacher Peter vintec, appear to be the target audience of the Raspberry Pi Foundation
True, but that is to be expected. In fact it was planned this way. The geeks stretch and test the Pi and generate a pool of knowledge/arguments/blogs/videos etc so the educators can pick over the pieces in the second wave. The second wave is just starting. Hopefully
a. It is incorrect to to say that the standard PC is not immediate or physical. In fact, the SoC Pi is more abstracted than the usual PC. It is more difficult to learn about how a computer works from the Pi.
A PC is a black box. You can see the Pi and its components. Most parents/schools do not want their kids dismantling the family PC. In many cases it would be dangerous to let them try.
b. It is not about cost or the lack of electricity in developing countries. See the Foundation's goals. To make the Pi a working computer need an additional investment at least five times the cost of the Pi, if you don't already have a PC. If you have a PC, you don't need a Pi, for learning. Without a good Internet connection, the Pi cannot be used.
HDMI monitors are only £80. I saw one in Tescos and that was without even looking for one. You can learn on a PC but you can't power it from AA batteries and strap it to a motorised platform. That is a huge learning benefit. No one is going to let a child drag the family PC into the shed to create a weather monitor. The Pi can be used without the internet. Once you've got the image you can write to an SD card and boot the Pi. No internet required.
c. It is not correct to say that you can't interface to external hardware easily with a PC. A PC is a computer, the Pi is a computer, and the PC has been around much longer and there are more interfacing options, and as cheap if not cheaper.
You've got a Pi, a PC, an LED and a resistor. You've got 2 minutes to make the LED blink. What do you choose? Even if you've got a parallel port you can't use it with Windows. The Pi is so much easier to interface to with almost no additional equipment. I'm not aware of any cheap ways of interfacing LEDs, buzzers and motors to a PC.
A school can not kit out a computer lab with second hand obsolete PCs running unlicensed copies of DOS. They need off-the-shelf equipment.
d. There is no issue with giving students full administrative control of a virtual machine. Students can freely re-image a virtual machine as often as they like without affecting the host PC. Almost a decade ago, I was in a Microsoft class on AD and Exchange. Each of the training PCs ran five Virtual Servers simulating the DCs and different Exchange Servers. Students are welcome to rip apart the VMs. At the end of the day, with one click, the trainer restored all the VMs to their original start state for the next day's class. That was in 2003.
I guarantee that training environment cost plenty of money and a huge amount of expertise to setup and maintain. Not to mention physical space. Much more complicated than writing the Raspbian image to an SD card. Not easy to set up in the school hall for an after-school Pi club! A training environment is also something that students can't replicate at home. It is also very desk bound and therefore boring. A Pi is more portable.
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