Hello, world! CS50's lectures in Sanders Theatre at Harvard University are open to the public, September 2025 – November 2025. Whether you are (or were!) a student or teacher of any of CS50's courses, or just CS50-curious, you are welcome to attend CS50's lectures in person in Cambridge, Massachusetts, USA. Fall 2025's lectures will become part of CS50x 2026 on edX.

To attend in person, visit https://cs50.ly/attend.

To watch online instead, register at https://cs50.ly/watch.

SCHEDULE

• Scratch on Wednesday, September 3, 2025 at 1:30 PM – 4:15 PM EDT
• C on Monday, September 8, 2025 at 1:30 PM – 4:15 PM EDT
• Arrays on Monday, September 15, 2025 at 1:30 PM – 4:15 PM EDT
• Algorithms on Monday, September 22, 2025 at 1:30 PM – 4:15 PM EDT
• Memory on Monday, September 29, 2025 at 1:30 PM – 4:15 PM EDT
• Data Structures on Monday, October 6, 2025 at 1:30 PM – 4:15 PM EDT
• Python on Wednesday, October 8, 2025 at 1:30 PM – 4:15 PM EDT
• SQL on Monday, October 20, 2025 at 1:30 PM – 4:15 PM EDT
• Artificial Intelligence on Friday, October 24, 2025, at 12:00 PM – 1:00 PM EDT
• HTML, CSS, and JavaScript on Monday, November 3, 2025 at 1:30 PM – 4:15 PM EST
• Flask on Monday, November 10, 2025 at 1:30 PM – 4:15 PM EST
• The End on Monday, November 17, 2025 at 1:30 PM – 4:15 PM EST