This is a study tool from Shinken Zemi that allows you to study on the Shinkansen (bullet train)! You insert the problem cards into the Shinkansen machine and use it! When you answer the questions correctly, the sound effects of the Shinkansen arriving at a station, going through a tunnel, and the sound of the train running on the tracks play, which my 3-year-old son really enjoyed! If you're interested, please feel free to purchase it☆ I'm also selling an educational toy for practicing kanji (Chinese characters) for second graders at a low price♪