Problem Sets
Problem sets are programming assignments that allow you to implement each week’s concepts in code. You may use CS50’s own AI-based software, including the CS50 Duck (ddb) in cs50.ai and cs50.dev, but no other AI-based software (e.g., ChatGPT, Claude, Copilot, Gemini, et al.).
The deadlines shown below are automatically converted to your timezone, based on the browser settings of the device viewing this page. In Gradescope, the assignments’ deadlines are always shown in Eastern Time (U.S.).
| Problem Set | Language | Release | Deadline |
|---|---|---|---|
| Problem Set 0 | Scratch | 2026-09-02T10:15:00-04:00 | 2026-09-08T23:59:00-04:00 |
| Problem Set 1 | C | 2026-09-09T10:15:00-04:00 | 2026-09-13T23:59:00-04:00 |
| Problem Set 2 | C | 2026-09-14T10:15:00-04:00 | 2026-09-20T23:59:00-04:00 |
| Problem Set 3 | C | 2026-09-23T10:15:00-04:00 | 2026-09-29T23:59:00-04:00 |
| Problem Set 4 | C | 2026-09-30T10:15:00-04:00 | 2026-10-06T23:59:00-04:00 |
| Problem Set 5 | C | 2026-10-07T10:15:00-04:00 | 2026-10-13T23:59:00-04:00 |
| Problem Set 6 | Python | 2026-10-16T10:15:00-04:00 | 2026-10-25T23:59:00-04:00 |
| Problem Set 7 | SQL | 2026-10-26T10:15:00-04:00 | 2026-11-01T23:59:00-05:00 |
| Problem Set 8 | HTML, CSS, JavaScript | 2026-11-02T10:15:00-05:00 | 2026-11-08T23:59:00-05:00 |
| Problem Set 9 | Python, SQL, HTML, CSS, JavaScript | 2026-11-09T10:15:00-05:00 | 2026-11-15T23:59:00-05:00 |
Problem Set Check-ins
After Problem Set 3 and 5, you will complete a Problem Set Check-in with a member of teaching staff to talk about one of your programs. This is an opportunity for you to interact with more of the teaching staff, as well as solidify your understanding of the wrote you’ve written.