Grade, Rank
きゅう
None
None
There are pieces of thread on each escalator showing you what level they go to in your school. Each escalator takes you to a different grade, so make sure you follow the right thread or you'll end up in a class that's either way above or way below your level.
You want to see what the highest level is, so you go up the wrong escalator. At the top you find a giant cucumber (きゅう).