Do schools need more security? A shocking and tragic attack on a teenager in Sheffield revives the debate about how to keep children safe.
Stabbed to death during lunch break
Youth detained: A 15-year-old boy, who cannot be named because of his age, appeared in court on Wednesday morning charged with the murder of Harvey Willgoose (above). Glossary
knife wands - Metal-detecting devices used by police to search for concealed weapons, such as knives.
NASUWT - National Association of Schoolmasters Union of Women Teachers.
Mentor - A person who helps a less experienced person learn and grow by providing guidance and support.
Ben Kinsella Trust - An anti-knife crime charity.