My son has a MacBook Air which was required for school (a).
However, it sometimes comes dangerously close to running out of power near the end of the school day despite the fact that we've (I think) set it up correctly for low power consumption.
I have suggested taking the power adapter to school, or even getting a second one to carry in his backpack) but apparently many of the classrooms don't provide enough wall sockets, or don't have them handy to the desks.
The local Apple store was spectacularly unhelpful given that they only sell such devices for non-laptops.
What's a good solution for him to plug into his laptop during recess/lunch to get the battery levels up to a point where he'll easily see out the day? Something that would give an extra one to three hours would be ideal.
Additionally, if anyone has some really good tips for lowering power consumption, I'd be happy to hear them though, of course, my question is really about a suitable power device.
(a) I asked if a Linux laptop would be okay and they said yes, but my son would likely get beaten up in the playground :-)