Talk:Episode 46/@comment-26962647-20160625135637/@comment-27736988-20160626030733

That's the transliteration of the Japanese title. 旅立ちのうた is read as "Tabidachi no Uta."

It's written on the anime's official Twitter feed that it's the insert song used in Episode 24, and it's sung by Class 3-E.

I think there's some confusion that the insert song is an already-existing or old song because of the title -- it's not. It's an original song with lyrics by Shōko Fujibayashi (also wrote the lyrics for Bye Bye YESTERDAY), and composed and arranged by Akimitsu Honma (also arranged Bye Bye YESTERDAY).

It's all found in the end credits.