I'm looking for a manga I've read before about a middle school girl who has a crush on her scientist dad's apprentice. He is a high school student so she goes into one of her father's machines and comes out looking high school age and until they find out how to fix it she has to attend high school. I think in the end she eventually turns back and the boy/apprentice promises to wait for her to grow up.

Thank you!

I am curious too.