"If you see a whole paper of red, it looks pretty frightening," said Sharon Carlson, a health and physical education teacher at John F. Kennedy Middle School in Northampton. "Purple stands out, but it doesn't look as scary as red."
A mix of red and blue, the color purple embodies red's sense of authority but also blue's association with serenity, making it a less negative and more constructive color for correcting student papers, color psychologists said. Purple calls attention to itself without being too aggressive. And because the color is linked to creativity and royalty, it is also more encouraging to students.