When I was in school (last year), they pulled the same thing... we "had" to lease laptops from the school, which were Toshiba Windows XP machines (heavy and clunky).
I had no choice in the matter; the school said it was part of the program and I "had" to use the Toshiba computers.
To say that the Macs will not work with the school network is both BS and true. It will work, but each computer is has some sort of ID and if your computer doesn't have permission to be on the server, the computer won't log in correctly.
I brought my Powerbook to school a few times, and it worked for basic internet stuff but I couldn't log on to the server because my computer was denied. The server contained teachers' notes, assignments, and other things for class.
In order for my Mac to work, I would need to register my computer into the system. The school, of course, refused to do that and said I must use their computers... blah, blah, blah (politics).
The school, by the way, had several Mac labs and they were testing ibooks with a few students, which worked fine and log into the server fine because those computers had the correct permissions.
So, a Mac will work fine... it's just that the school didn't want students to have the choice to use their own computer. We had the choice of lab computers or our school issued (and leased) computers. By the end of the lease, you end up paying double the price of a new laptop!
The school, therefore, made us get the Toshiba XP machines not because my Mac is incompatible, but they had a deal with Toshiba to make every student lease their computers. In turn, the company gave kickback to the school and the school made money off the leasing process.
Students, by the way, could not keep their leased laptops after they left school. Well, there was an option to buy the laptop at full retail price but with all of the software cleaned off it. So, you end up paying triple the price for a older, used computer (not worth it).
To be fair, the laptops came with software needed for the class... in my case, Microsoft Office, Pagemaker, and Illustrator. We eventually just ended up using Office because we got into Quark Xpress and Adobe CS on the Mac machines. I was lucky enough that I could do my homework on my Powerbook, while others had to book lab time.
So, I'm went to school using the Toshiba in half of my classes for notes and getting assignments off the server (oh, and using Messenger and games, stuff teachers hated because students were doing that all through class). And, the other half of my classes were on a Mac computer, using it to design layouts and work on photo stuff.
Kick-backs and school branding are becoming really popular now. Our school, for example, only sold Coke and Coke-related products. You couldn't find any thing Pepsi or Pepsi-related on campus. Same with other things that were sold around school. Large companies pay big money to brand themselves into the school and into student's lives.
I hate to say it, but your son will most likely be forced to use what the school says because of politics and marketing, not because the ibook "can't work."
And, it wouldn't even matter if you had a Windows laptop or even the exact same brand... most likely they are going to direct you to a certain reseller or lease it through the school IT department. I had several friends with Windows-based laptops that were told, "you can't use that computer -- you must use the one we say you should use."
Politics. Branding. Money. That's what it's about.
--nate
P.S. Don't ditch the iBook, keep it at home. If his school was anything like mine, they wouldn't let student keep the laptops over winter/spring break or during the summer unless you paid an extra fee. So, the iBook will be handy then, and no doubt, your son will probably use the iBook outside of the classroom environment for other things.
