YOU SAID:

I was gonna go to class, but then I got high.

INTO JAPANESE

クラスに行くつもりだったが、高いそこ。

BACK INTO ENGLISH

Was going to go to classes there.

INTO JAPANESE

そこのクラスに行くつもりだった。

BACK INTO ENGLISH

It was going to go to classes there.

INTO JAPANESE

それはそこのクラスに行くつもりだった。

BACK INTO ENGLISH

It was going to go to classes there.