Sources, textbook images & validation
Source quality and source selection strongly influence output quality. This session teaches you to choose sources deliberately and validate what NotebookLM actually understood.
NotebookLM currently accepts copied text, Google Drive files, supported image formats, PDFs, DOCX, PPTX, CSV, websites, audio, ePub files and public YouTube URLs. Free-account limits exist and change — validate what matters, don't memorise quotas.
The CLEAR test — run it on every source
Can the text, Telugu script, equation, table or diagram actually be read?
Does this source directly support what you want students to learn?
Is it a textbook, official curriculum resource or teacher-approved reference?
Does it suit the intended class?
Enough useful content, without unrelated material creeping in?
👀 Watch the demo — three versions of the same page
- A blurry textbook photo Ask: "Identify the page title, headings, definitions, examples and diagrams." Watch what gets missed or misread.
- A clear textbook photo Same question. Notice alignment, lighting, Telugu character clarity, equation readability, diagram labels.
- A searchable PDF Same question again. Compare completeness. This is why source quality comes before prompting skill.
Photographing textbook pages properly
- One page at a time where possible; keep the page flat.
- Hold the camera directly above the page — avoid shadows and glare.
- All four corners visible; crop away the table, floor and hands.
- Check Telugu letters, units, formulas and table labels are readable.
- Retake blurred photographs. Two clear pages beat ten poor ones.
Know your source types
| Source type | What to remember |
|---|---|
| Webpage | Provides imported page content — confirm what was actually captured. |
| Public YouTube URL | Relies heavily on the transcript; don't assume every visual detail came through. |
| Image | Visually interpreted — clarity decides everything. |
| Google Drive file | Needs permission and access to remain available. |
| Second source next to a textbook | Add it only when it adds genuine value. |
🖐 Now you do it — validate a source
Add one source of your own (your textbook chapter). Then run these validation prompts and note what NotebookLM recognised correctly and what needs caution.
"Would adding ten more sources improve this notebook — or make its purpose less clear?"
Sources should be selected intentionally. More sources do not automatically mean better output. A notebook should serve one clear lesson or resource purpose.
✋ Checkpoint — show your trainer
Checkpoint complete — your sources are trustworthy!