Doraemon Movie 16: Nobita no Sousei Nikki

Nobita has no idea what to choose for his summer research project, so Doraemon gives him a World Creation Set that lets him build and observe a miniature planet from its very beginning. What starts as an easy way to finish homework soon fascinates Nobita, Shizuka, Gian, and Suneo as life appears and entire civilizations develop before their eyes.

Their artificial world eventually becomes complicated enough to create dangers of its own, while a separate disturbance involving forbidden time travel draws the attention of the Time Patrol. Nobita's school assignment turns into a genuine adventure as the friends try to protect the world they have watched grow and rescue one another from trouble far beyond a simple diary.