A work machine? I thought you were in school?
I worked whilst I was at school.
If you feel the need to play with Ubuntu and or Windows and you're on a budget the recently announced $35 RaspberryPi 2 can run Linux and seems like a version of Windows 10.
Your fantastic suggestion assumes the following:
1. That he doesn't need anything more than a pitiful amount of RAM (1GB)
2. That he doesn't need a CPU that even remotely approaches desktop standard.
3. That he is happy running his OS from a slow SDCARD.
4. That he doesn't need any other sort of fast directly attached storage (USB2)
5. That he is happy using only the very small selection of Linux distros which will run on RPi
6. That he does not require any x86 software.
Colleges often allow only certain calculators to prevent cheating and keeping exams fair. It would appear your school is doing the same thing.
How is this even remotely the same thing. The stipulation on calculators (at least in my experience) has only even been during the actual exam and this isn't a throw-away $50 calculator, it's a laptop costing thousands of dollars.
Are you purposefully being obtuse?
How about the best reason of all, that it is HIS property
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I'm sure once you've graduated they'll be happy to unlock it.
Why are you sure? What if they don't? What if they don't adequately protect the password and they lose it?
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It may seem somewhat draconian at first glance (especially with the way that you are reacting here), but looking at it from the perspective of the school's IT department, it does start to make sense to me.
Doing this prevents a student from doing things to the laptop that would otherwise pose a support nightmare for the IT personnel.
No, it doesn't make any sense for them to forcefully do this to student property.
Firstly, you're assuming the school is providing some form of support. Secondly, a simple "if you do not allow your firmware to be password protected your laptop becomes completely unsupported by school technicians" clause would be completely sufficient.
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If you feel the need to play with Ubuntu
I think if he is using it for work it doesn't qualify as needing to "play" around with Linux.
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What should I do? This isn't just affecting me, it's affecting the whole school!
Get your parents involved - You will need their support if you defy the school. Explain the situation to your school about needing the MBP for non-school activities and explain that you do not expect, nor will you request any support of any kind from the school for the laptop.
If all else fails, just refuse.