If "jotter" refers to a small notebook:
* Carnet: This is the most common and general term.
* Bloc-notes: This is another common term, often used for a notepad with adhesive pages.
* Cahier: This word is used for a bound notebook, but it can also refer to a school notebook.
If "jotter" refers to the act of writing down notes:
* Noter: This is the most common verb for "to jot down."
* Griffonner: This is a more informal word that implies quick or casual writing.
* Annoter: This verb specifically implies adding notes or comments to something.
The best translation will depend on the specific context and the nuance you want to convey.