Many schools across the country have rules about tech in the classroom, but they’re not the rules you might think. Teachers instruct students to take out their smartphones, to power up their iPads, and to log in to Twitter, the Huffington Post reports. The teachers and administrators featured in the slideshow below are tapping into the potential that tech tools hold for education. They’re using smartphone apps to teach the laws of physics, iPads to practice penmanship, and Foursquare to guide students around unfamiliar college campuses. Digital whiteboards and e-clickers add an element of interactivity to tests and quizzes…