@Sunirose, before submitting any term papers or doing any presentations, have you had your sims edit their term papers or organize their presentations? Plus a little thing I discovered, if you hover over either the menu option of editing term paper or on the presentation board, it will tell you if it's poor, normal, excellent or outstanding. (see below) I too had my first sim do poorly in his first term, it wasn't until I played my second sim when I discovered how to tell how well her term papers or presentations were. Once I learned of this, she has done much better in her classes.
https://i.imgur.com/12NtU1L.png