CS50 Handbook

David J. Malan
malan@harvard.edu
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CSCI S-50 Summer 2025
CSCI S-1b Summer 2025
CSCI S-80 Summer 2025
CSCI S-159 Summer 2025

CS50 AP 2025–2026
CS50x 2025

CSCI E-5a Fall 2024
CSCI E-23a Fall 2024
CSCI E-33a Spring 2025
CSCI E-151 Spring 2025

Status Page

Communities
Bluesky
Clubhouse
Discord Q&A
Ed Q&A
Facebook Group Q&A
Facebook Page
GitHub
Gitter Q&A
Instagram
LinkedIn Group
LinkedIn Page
Medium
Quora
Reddit Q&A
Slack Q&A
Snapchat
SoundCloud
Stack Exchange Q&A
Telegram
TikTok
Threads
Twitter Account
Twitter Community
YouTube

Courses
CS50x
CS50 AI
CS50 Business
CS50 Cybersecurity
CS50 for Lawyers
CS50 Python
CS50 R
CS50 Scratch
CS50 SQL
CS50 Web

Grading and Feedback for Pset5: Speller

Grading Guidelines

Speller
- Guidelines
- Staff Solutions