Why does the tip of my pointer finger become tingly when im taking notes in class?

Most likely it's caused by pressure on a superficial nerve in that finger if that's the only time you experience the symptom Try different positioning of the pen on your pointing finger.

Sometime if one is holding the pen or pencil too tight, that can cause pressure on the finger tips. Sometimes, it is the Shape and Consistency of the writing material that does it. One should try different pens/pencils and if symptoms persist see PCP for evaluation.