I have had to register to reply to this! Very long time lurker, and you have drawn me out!
I have a wee photography business, and I do a bit of school work. The biggest issue for me is the big companies who's packages are over priced and who can give 35% commission back to the school. My cheapest pack is under £10 for 2 framed prints, and I offer 10% commission to the school.
Not only do we have to pay commission, we have to pay for prints, frames, upkeep of our equipment, then obviously tax etc on top of that.
It's not a couple of hours work. The last school I did had 150 pupils. I was at the school from 830-330. Then spent at least 3 days processing the images, then printing and delivering proof sheets to the school was another' days work. Then when the orders come in there is another days work involved touching up images, placing orders for prints and frames. Then when you have the prints and frames the orders have to be packaged and delivered to the school. So that's probably another half day.
Last school I took around £1500 in sales. £150 back to the school. Then frames and prints were another £300. So before tax and insurance that's £1050 And that was one of only 2 jobs that month. The second job was a small playgroup that brought me about £300 before tax after costs were paid.
Also the big companies pay their photographers a very basic salary and top it up with commission. The photographer sees very little of the money!
When it comes to copyright, the photographer owns the rights to any image taken, if you buy a digital image you normally are given a limited rights release. Allowing you to print but not alter the image, but photographer still owns the image.
If you want good and reasonably priced photographs, ask your school to expand their horizons and take on a local photographer, rather than a big company who don't care about the end product!
I shall get off my soapbox now! 