The overall simulation of station elements is the theme. There are 5 trains in the station, and the front of the train is the theme building block. The carriage is the content building block, which is easy to distinguish the distribution of the theme and the content. When children use products, they fill up their knowledge like station staff. After pressing the full submission, the "station" will emit the sound of the small train departure and the flashing light, implying that the knowledge will be fully loaded.