Not knowing much about cameras, what resolution would you use for school cameras that are used for general photographs around school, ie not specialised 'arty' stuff. The photos are printed out on the laser colour printer and used mainly for displays. Staff use the xp print wizard but I'm concerned that huge weighty photos are being printed and taking up bandwidth and using toner.
We make them as low a resolution as we can - in my experience it is trial and error and really depends on the sort of picture that it is. The problem always is that the staff will change the resolution anyway so it is a hard thing to police unless you take all the pictures yourself
We have some 3 and 4 megapixel cameras that produce perfectly good pictures
I just purchase whichever seem to be the best value with the best specification. I purchased some kodak 6 megapixel cameras with free 2GB SD cards free for about £50 each. They had a 3x optical zoom and could record video in quicktime with sound (useful for imovie editing).
I just tended to try and stick to standards, eg standard usb connections, sd cards etc. just made it easier to find stuff to fit them later. Just unfortunate that kodak's USB cameras didn't have standard USB connections. They just look very close to mini USB.
There's little point in having high resolution digital cameras when using laser printers to print the images. Colour laser printers generally have less colour range (gamut) than a decent photo-inkjet printer and tend to be fed on cheap & cheerful 80gsm matt paper. They can be used to produce images that are perfectly acceptable in wall mounted displays etc, or when viewed at arms length. I have been quite impressed with the images produced on our HP Color Laserjet printers at school, particularly the latest models.
From personal experience, a decent 6 megapixel point and shoot camera will produce good quality results when printed on a photo-inkjet on 10"x8" glossy photopaper. You are unlikely to improve on this using a laser printer, even with higher resolution. All that will happen is the printer will spend more time throwing pixels away.....
In fact too many pixels on the image sensor in the camera can cause more 'noise' in the image, especially with poor lighting and high ISO settings. This is more of a problem with the smaller sensors in typical 'point and shoot' cameras when compared to much larger sensors in digital SLRs. I am afraid there is a certain amount of competition between camera manufacturers in the bragging rights game over who can cram the most megapixels into their products.... they then have to spend more time in-camera trying to suppress noise.....
I would look for cameras that have the following:
SD or SDHC memory cards, a lot of laptops/netbooks come with SD card readers built-in
USB connection (most do now)
Image stabilisation (IS) if possible
optical zoom range 3:1 to 5:1, anything longer can lead to blurred images even with IS
Other points of consideration:
Don't pay too much attention to digital zoom, it just plays games with the sensor.
Sony cameras use a more expensive memory card format
Watch out for LCD screen size; the bigger the screen the more fragile it can be & the heavier the battery drain.
Many cameras now offer video (with audio) recording capabilities too, at my school we have found this to be handy and much less fragile than camcorders
We bought cheapo used Olympus cameras off ebay for a few quid (1 & 2 Mp) - they are fine for general use, with the added bonus that no one wants to steal them.