The vast majority of physical keyboards sold for iOS devices these days are of the Bluetooth variety, but not the newest keyboards by Griffin. They're wired. The two new keyboards, one with a Lightning Connector, the other the old-school 30-pin dock connector, are meant primarily for educational use, as there's no need to bother with pairing — just plug it in and go.
Bluetooth keyboards understandably present a few problems for schools. They're yet another device to be charged or have fresh batteries put in, they have to be paired with an individual device, and our mercy on the poor teacher that has to deal with a set of iPads and keyboards dumped on his/her lap and not matched with their paired keyboards.
A wired keyboard, as Griffin notes, solves that quite simply. There's no pairing, there's no charging, there's no wondering about which keyboard is paired with which tablet. You just plug it in and start typing. Additionally, the keyboards help maintain compliance with SBAC and PARCC testing requirements, which prohibit external wireless connections during the test administration process.
The Griffin Wired Keyboard is available now from Griffin.com for $59.99.