Requitan!

"Rekitan!" is a sci-fi manga about an elementary school boy who loves history and a creature from the future with a time machine that flies to various eras and overcomes incidents and problems with historical figures. Cases are turned into big things, future villains get in the way, and where the main characters are going is always exciting. The thrilling development will make the readers enjoy reading as if they were jumping into history. There is also a commentary page of the historical figures that appear, which helps to further deepen the understanding of history.
Volume 1 contains four works: "Iemitsu Tokugawa and Sankin Kotai", "Prince Shotoku and the Twelve Ranks of the Crown", "Imoko Ono and the Envoy to the Sui Dynasty", and "Tadataka Ino and Survey".