Both the Massachusetts Institute of Technology and Harvard offer online mathematics courses. These courses vary in terms of difficulty, course length and types of user interfaces.
The Massachusetts Institute of Technology features a extensive list of free courses. Since the needs of students of mathematics vary, the institute's department of mathematics recommends that students try exploring different branches of the academic discipline. This includes studying both applied and pure mathematics. Those who are seriously interested in the study of math are encouraged to take some of the advanced seminars.
As of 2015, MIT's available online courses were recorded as early as 1999 and as recently as 2013. Available courses include Single Variable Calculus, Calculus with Theory, Differential Equations, Mathematics for Computer Science, Introduction to Functional Analysis, Geometry and Quantum Field Theory, and Nonlinear Dynamics I: Chaos.
The Harvard Extension school offers courses both on campus and online. These courses require students to pay tuition. The online options are specially designed to allow students to make degree progress without necessarily being on campus. Available courses are broadly divided into general mathematics, mathematics for teaching and related courses. Course offerings include Quantitative Reasoning: Practical Math, College Algebra, Precalculus, Linear Algebra and Classical Geometry.