Find the id and first name of the student that has the most number of assessment notes?
SELECT T1.student_id ,  T2.first_name FROM Assessment_Notes AS T1 JOIN Students AS T2 ON T1.student_id  =  T2.student_id GROUP BY T1.student_id ORDER BY count(*) DESC LIMIT 1
most number of assessment notes refers to MAX(COUNT(assessment_notes)); id refers to student_id; first name refers to first_name; join condition is on matching student ids between Assessment_Notes and Students tables;