The confusion is that the article refers to two different courses: "18.30, differential equation, the largest mathematics course at MIT, with more than 300 stu

The confusion is that the article refers to two different courses: "18.30, differential equation, the largest mathematics course at MIT, with more than 300 students" [ths might be the course that is now 18.03] "18.313, a course I teach in advanced probability theory"