All good things about Macs in education, unfortunately they're nothing more than anecdotal accounts.
What many folks will only look at are the impact on test scores. Hard numbers.
Before you jump,I was involoved in the computers in our local school district and saw this argument all the time which the districts tech coordinator had to defend. And he was a PC guy when he came to the district, but looked at the numbers. Macs were more cost effective by no small margin.
After that, it was an issue of teacher training and most importantly, how well(or not) a teacher integrated technology into their daily lesson plan.
In many schools today, Mac or not, many teachers fight technology. They contend they're already overworked and underpaid so they resist new learning. Their plate is full. But they miss the notion that technology can make more time for them, ease some of the more tedious aspects of learning and be such a great window to information which is a foundation of learning.
Then there's the aspect of making learning fun and engaging the students...
Just my $.02
Do Apple Products Really Enhance Education?