curriculum actually became law are. tara kirkland explains how. a little bit of success one time around. reporter: students in this ap government class were already civil rights champions. for three years, the new jersey teens had researched, drafted and even tweeted to the president to turn their class lesson into federal law. it was an incredible moment. reporter: but when they heard the news the cold case act was a approved, mr. wexler knew history had been made. this is something way outside the normal scope. to the best that we can find, no teacher, to class, no set of students have ever done this before. reporter: the new federal law will allow investigators to review reports of murders from the civil rights era and as far back as the 1940s, believed to have been racially charged. the information is out there, it s sitting out there. it s just not available to these people. and i really just felt like they needed to know. i know if it was me, i would want to know.