Lol, Android tablets and phones have better specs than iPads and iPhones more often than not...
The OS is fragmented to hell with all of the different skins used by manufacturers instead of stock Android (see: TouchWiz, Sense UI, etc.), but it's pretty simple to simplify the user interface with the use of custom launchers, lockscreens, icon packs, etc.
Like Vendetta said, different manufacturers make differing devices to give consumers options depending on what they want in a phone or tablet. This isn't a bad thing.
If your school's devices are having issues with display sensitivity and responsiveness, I'm willing to bet that it's a low(er)-end device or running a bugged up version of Android.