YOU SAID:

I am not doing well in my classes

INTO JAPANESE

私は自分のクラスでうまくいっていません

BACK INTO ENGLISH

I'm not doing well in my class.

INTO JAPANESE

私はクラスでうまくいっていません。

BACK INTO ENGLISH

I'm not doing well in class.

INTO JAPANESE

私は授業中はうまくいっていません。

BACK INTO ENGLISH

I'm not doing well in class.