Teachers lose evenings to planning that AI can draft in minutes — if the prompts are built for classrooms. The ChatGPT Teacher's Assistant is 20 copy-paste prompts across the teaching week: (1–5) 45-minute lesson plans, 3-week unit architects, lesson hooks, explanation simplifiers, and 10-minute sub plans; (6–10) quiz builders, differentiated worksheet sets, rubric writers, exit tickets, and review games; (11–13) feedback comment banks, essay feedback accelerators, and grading calibration; (14–17) discussion questions, project menus, vocabulary systems, and brain breaks; (18–20) parent email templates, conference prep sheets, and newsletters in minutes. Every prompt ships with tool settings (ChatGPT, Claude, Gemini), a negative prompt that blocks wrong answers and busywork, and a variation — 40+ classroom workflows from one pack. Kills Sunday-night planning dread and the feedback backlog. Works with any chat AI; student privacy rules built into every prompt.