Tamako tells Nobita to complete his homework before he goes out to play. Doraemon helps Nobita with his new echo mountain gadget, but Nobita misuses it on his mother when she falls asleep and steps out to play. Nobita uses the gadget against Gian, as he never sticks to his words. After Nobita and Doraemon return home, Tamako yells at Nobita and makes him complete his homework.