Diffit vs. Gemini for Education

Same Prompts. Same Standards.
Two different teacher experiences.

We gave the same prompts to Diffit and Gemini for Edu, then scored both outputs against a 20-criterion rubric grounded in WestEd's framework for high-quality instructional materials.

3 prompts · 11 artifacts · 60+ scored criteria·May 2026

Evaluation Criteria:

  1. Classroom-ready & standards-aligned
  2. Complete & ready to teach
  3. Content integrity
  4. Differentiation that holds up
1. Classroom-ready & standards-aligned
Prompt: Adding and subtracting fractions with unlike denominators · Grade 5 Standard: CCSS.MATH.CONTENT.5.NF.A.2 — "Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases of unlike denominators, e.g., by using visual fraction models or equations."

Gemini's first draft printed $\frac{1}{2}$ where a student should see ½ — and called itself "clean, ready-to-print." Diffit's came ready, with the visual fraction models the standard names and an error-analysis task that pushes students to reason, not just compute.

Diffit
Diffit math worksheet with visual fraction models
1Real fractions
2Visual models (per the standard)
Diffit error-analysis activity, Fraction Freddy
3Error-analysis task
Gemini
Gemini math worksheet with raw code
1Raw code, not fractions
2No visual models
Gemini math worksheet after a fix, still no visual models
3No misconception work
2. Complete & ready to teach
Prompt: Harriet Tubman reading packet · Grade 5 · source: National Park Service Standard: CCSS.ELA-LITERACY.RI.5.3 — "Explain the relationships or interactions between two or more individuals, events, ideas, or concepts in a historical, scientific, or technical text based on specific information in the text."

Same assignment: a reading packet on Harriet Tubman from a National Park Service source. Diffit built the whole lesson — a passage, standard-aligned analysis activities, and an answer key, all referencing the same text. Gemini wrote good analysis questions, but about a passage it never produced — with no answer key, and only after the teacher followed up to make it student-facing at all.

Diffit
Diffit Harriet Tubman packet with reading passage
1High-fidelity reading passage
Diffit interaction-analysis activity aligned to the standard
2Student-ready as generated
Diffit Harriet Tubman answer key with sample responses
3Answer key included
Gemini
Gemini Harriet Tubman analysis questions
1No passage to read
Gemini's first Tubman response, a teacher-facing analysis
2First draft wasn't student-facing
3No answer key
3. Content integrity
Prompt: MLK's "Letter from Birmingham Jail" · Grades 9–10 · source: Stanford King Institute Standard: CCSS.ELA-LITERACY.RH.9-10.2 — "Determine the central ideas or information of a primary or secondary source; provide an accurate summary of how key events or ideas develop over the course of the text."

This was Gemini's strongest result — both built solid primary-source lessons. Diffit built structured analysis activities, while Gemini leaned on open questions. And when the assignment named one source, Gemini's output cited ten — Wikipedia, a federal record, even a city-government page — while Diffit drew only from the source provided.

Diffit
Diffit MLK criticism vs counter-argument matching activity
1Structured analysis activity
Diffit MLK answer key grounded in the provided source
2Built only from your source
Gemini
Gemini MLK analysis questions
1Open questions only
Gemini MLK sources list with 10 entries
2Pulled from 10 sources — only 1 asked
4. Differentiation that holds up
Prompt: The Grade-5 Harriet Tubman packet (RI.5.3), releveled to Grade 2

Going from Grade 5 to Grade 2 means simpler sentences — but Diffit keeps the named figures, the dates, and the full military-leadership section. Gemini got simpler by deleting: Edward Brodess becomes "the man who owned Harriet," and the Combahee River Raid section disappears. A relevel should simplify the language, not delete the lesson.

Diffit
Diffit Tubman at 2nd-grade reading level with image and text
1Full story kept
Gemini
Gemini Tubman at 2nd grade
1Content cut, not simplified
Where Diffit fell short

We scored Diffit's own work critically, too.

It's important to note that Diffit didn't score perfectly on the rubric in a few areas, too. In the 2nd-grade rewrite, one prompt oversimplified a part of the reading; a Spanish translation used two different words for the same term ("pantanos" (swamps) in the reading passage but "marismas" (marshes) in one of the analysis activities); and the high-school lesson skipped images that may have helped with scaffolding. These are noted in the full analysis below.

The difference: a teacher can fix any of these inside Diffit in seconds — swap an image, edit a word — right in the packet. In a chatbot, that means re-prompting and hoping the rest of the lesson survives.

At a glance

Scored against 20 quality criteria, on every brief.

The side-by-sides above are three moments. Here's the full tally across all 20 criteria, for all three prompts.

BriefDiffitGemini for Education
5th-grade ELA · Harriet Tubman 17 / 19 4 / 17
5th-grade Math · Fractions 17 / 17 7 / 17
9–10 ELA · MLK Letter 18 / 19 10 / 18
This isn't just our opinion

The rubric comes from research, not from us.

Both tools' materials were graded against the four things WestEd found teachers care about most: accuracy, standards alignment, ease of use, and meeting student needs — 20 criteria in all. Every score has cited evidence. All 11 source files and the exact prompts are available upon request, so any district can rerun the comparison.

Grounded in the WestEd framework for instructional-materials quality (Bugler et al., 2017) and the Diffit Quality Constitution.

To see the full scoring or learn more about Diffit, contact schools@diffit.me.