Doremi and her best friend Hazuki Fujiwara want to swap lives for a day, as they both feel that the other is luckier. However, this leads to a few consequences.

A new girl named Aiko Senōō from Osaka transfers to Doremi's class and unintentionally upsets Doremi and Hazuki at first. Once Doremi gets to know her, she befriends her and tries to find ways to cheer her up on Parents' Day at school.

Hazuki and Aiko find out Doremi's secret of being a witch apprentice after the stunt she pulls on Parents' Day, so they must also become witch apprentices to protect Doremi. The three girls redecorate the magic shop with a more cheerful design after Doremi accidentally destroys the shop.

After fixing up the magic shop and dubbing it Mahōdō, the girls await their first customers and are visited by a singing witch wholesaler Dela.

Nobuko Yokokawa is a liar in the girls' class, but nevertheless amuses everyone with her imaginative stories. When Aiko believes in her and realizes she lied, she becomes very hurt.

The three girls prepare to take their first witch exam, but Doremi must spend the day supervising her younger sister Pop. Pop wants to go to her grandparent's house by train by herself. When it comes to exam time, Hazuki and Aiko earn fairies for passing the exam. Doremi fails the exam, so she doesn't get a fairy.

After failing to pass the level 9 exam, Doremi is given another chance. Her goal is to find medicine for Motamota. Luckily, Doremi passes and gets her fairy, but she does it with the help of Aiko and Hazuki, who come to see her out of worry.

Doremi's fairy Dodo runs off after being scolded, so the girls use their new magic spell, Magical Stage, to try and find her.

Miss Seki and the vice principal drop by the magic shop after photos of the girls working there arise.