Legal analysis: children need to buy high-speed rail tickets. If they don't buy tickets, there is no way to prove that the children bought tickets, so the children can't enter the station.

Legal basis: Article 5 of the Law of People's Republic of China (PRC) on the Protection of Minors, patriotic education bases, libraries, youth palaces and children's activity centers shall be open to minors free of charge; Museums, memorial halls, science and technology museums, exhibition halls, art galleries, cultural centers and other public places shall be open to minors free of charge or with preferential treatment in accordance with relevant regulations.