‘18.701: Algebra I’

Table of contents

  1. Course Info
  2. Realistic Prerequisites
  3. Subject Matter
  4. Course Staff
  5. Lectures
  6. Problem Sets
  7. Exams
  8. Resources
  9. Grading
  10. Advice to Future Students

Course Info

Class Size 160
Hours/Week 11.9 (86 responses)
Instructors Henry Cohn
Overall Rating 6.5/7.0

Realistic Prerequisites

  • Students agreed that previous experience with proofs (e.g. from 18.100x) is necessary, but the course is self-contained when it comes to mathematical content.
  • Background knowledge in linear algebra is not strictly necessary. However, many students considered it to be helpful, since concepts like matrix multiplication are introduced very quickly.

Subject Matter

  • 18.701 is an introductory class. Most thought the content was very abstract and theoretical.
  • Lectures occasionally included applications to other areas of math and physics, which students described as interesting and useful.

Course Staff

  • Every respondent was enthusiastic about Professor Cohn. He was variously described as caring, approachable, friendly, accessible, and understanding.
  • Course staff were easily available at most hours over Discord, and many considered office hours to be helpful as well.
  • It was easy to get an extension or receive help when needed.


  • Lectures were engaging and helpful. Most were okay with the pace, but some thought it was a little fast.
  • Lectures were the main source of course content for most students. The textbook and lecture notes were useful supplements.

Problem Sets

  • Students generally described problem sets as fun and interesting, but also challenging and time-consuming.
  • A significant fraction of students considered the problem sets to be too long or too difficult.
  • Problems built on each other. Hints for each problem were provided on the class Discord, which were considered very useful.
  • Working with others was useful. Many said it was essential given the difficulty of the problem sets.


  • Exams were considered easier than the problem sets, but still challenging. Exams were take-home rather than in class, but there was still a time limit.
  • Exam structure was clearly explained beforehand, with some problems drawn from previous lecture and problem set content, and some new problems. Many students said that memorizing lecture results and their proofs was necessary.
  • Many thought the second exam was more difficult than the first.


  • Some students preferred to read the course lecture notes while others preferred the textbook (Algebra by Artin). Both were considered well-written and useful overall.
  • The class Discord was also a useful resource for getting questions answered.


  • Grading was generally considered fair and lenient.

Advice to Future Students

  1. “Take it with professor Cohn”
  2. “Start the psets at least 3-4 days in advance minimum”
  3. “Get Henry Cohn as your professor, or find lectures with him”
  4. “Find a group to work on the psets together and don’t be afraid of asking for help.”