I too use Mac's in the classroom and I have an older Epson scanner. I have
found that what you need is a (SCSI) scanner so that it will be compatable
with a Mac. Some scanners will have both kinds of software and can be used by
both formats. I have a UMAX at home that is a SCSI model and it will work
with a Mac as well. I would also recommend that you find one that is sturdy
and reliable for student use. HP makes a good scanner, UMAX, and others that
support the scsi port.