At Mother of Sorrows Catholic Church in Murrysville, Pa., on Wednesday evening, worshipers held candles as they prayed for those injured in a stabbing attack at the local high school. Connor Mulvaney /Pittsburgh Post-Gazette/Landov hide caption

itoggle caption Connor Mulvaney /Pittsburgh Post-Gazette/Landov

Emergency responders gather in the parking lot on the campus of Franklin Regional High School in Murraysville, Pa., on Wednesday after an attack there left at least 20 people, nearly all of them students, injured. Most suffered stab wounds or lacerations. Keith Srakocic/AP hide caption

itoggle caption Keith Srakocic/AP

Uintah Elementary School in Salt Lake City, where up to 40 students were served lunch Tuesday — only to have it discarded. They were told they didn't have enough credit on their accounts. Google hide caption

itoggle caption Google

Very few girls get the recommended 60 minutes of exercise daily. But physical activity could help with school, a study says. evoo73/Flickr hide caption

itoggle caption evoo73/Flickr

Crowdsourcing tools are giving teachers and school district employees more say on big decisions. iStockphoto.com hide caption

itoggle caption iStockphoto.com