Quick answer. Tell the model “45 minutes, three segments that sum to 45.” Then force a hook, one teach/try block, and a close with an exit ticket. If the draft runs 90–120 minutes, it is a unit sketch—cut it before you print.
A teachable 45-minute skeleton
- 0–8 min — Hook / access: phenomenon, retrieval, or language preview (including ELL stems).
- 8–35 min — Teach and try: mini-lesson plus one lab, text, or problem set. Materials listed by name.
- 35–45 min — Synthesize and check: share-out + exit ticket aligned to the objective.
Times are targets, not scripture. The rule is they add up and leave a close. Many AI drafts skip the close or invent a second day’s worth of stations.
Prompt that prevents unit-bloat
Include: grade, subject, exact minutes, grouping, materials you have, ELL/IEP notes, and “do not exceed 45 minutes; do not add homework unless asked.” If you want NGSS/CCSS, name the framework and grade.
Do this after generate
- Add the three times. If they exceed 45, cut a station, not the exit ticket.
- Strike materials you cannot get tomorrow (hot plates, rare kits).
- Rewrite the objective as a student-facing “I can…”.
- Write the exit ticket so it measures that sentence only.
Do it in MyLesson.AI
Open Create, enter the topic, and edit the timed script. On Pro, save and export or add a quiz from Teacher Tools. See also How to create AI lesson plans.
Citation-ready framing
Thesis. A usable AI lesson for one period is three segments that sum to about 45 minutes with a real close—not an untimed multi-day unit labeled as a lesson.
Suggested reference: MyLesson.AI. (2026). How to Build a 45-Minute Lesson Plan With AI (Segment-by-Segment). https://www.mylesson.ai/blog/how-to-build-a-45-minute-lesson-with-ai