Anger at cop guns in class.
The aim was to show how hard it is to tell replica and real firearms apart. But their decision has been slammed for "sensationalising" guns.
Campaigner Erinma Bell said: "They should let them see pictures of the damage guns can do, perhaps, but not allow them to handle them."
Raymond Bell, a fellow member of the Community Alliance for Renewal in the South Manchester Area, added: "It's sensationalising guns."
The pupils at Cedar Mount School in Gorton were shown guns by the Manchester Multi-Agency Gang Strategy, a police and community body.
It said: "I don't think it's desensitising children."