The problems that led to the school shooting at Arapahoe High School two years ago aren't unique. That's according to several new independent investigations. We explore the steps some say Colorado schools need to take to make them safer. Then, another challenge schools and students face: bullying on social media. A new play shows the pain it causes a teenage girl and her mother. Also, scientists think they've found a 9th planet in our solar system, but one astronomer says, "show me." And, why researchers are worried about a 1,000-year-old glacier west of Boulder.