This was the first full week back for students at the covenant school in nashville. the site five months ago of a mass shooting that took the lives of three students and two adults. it did prompt a special session from lawmaker this is week, but so far the tragedy has yielded few legislative solutions. active shooter training saved lives at the school. gary tuchman has more on the man behind it. reporter: whitney aerr heart and have been told to listen for a noise from another part of their school building, this noise. [ sound of gunfire ] reporter: this is the instructor of an active shooter training program who wants school employees to know gunshots don t always sound like gunshots. to be aware, they sometimes sound like someone working on a construction or, like, a repair