> ## Documentation Index
> Fetch the complete documentation index at: https://docs.learningcommons.org/llms.txt
> Use this file to discover all available pages before exploring further.
# Critical Thinking
> Rate a student's source-based argumentative essay (grades 8–10) for critical thinking across five indicators plus an Overall rating, with evidence quotes and reasoning.
[Evaluator last updated September 3, 2026.](#evaluator-release-history)
## Overview
The Critical Thinking evaluator rates a student's source-based argumentative essay for critical thinking, treated as distinct from writing quality.
Given the essay, the assignment prompt, and the source passage(s) the student was given, it returns a rating for 5 indicators:
* Evidence strength
* Synthesizing sources (if more than one source is provided)
* Counterarguments
* Facts over opinions
* Drawing conclusions
The evaluator also returns an "Overall" rating, with evidence and reasoning included for all ratings.
## At a glance
| | |
| :------------------- | :----------------------------------------------------------------------------------------------------------------------------- |
| **Inputs** | Student essay, assignment prompt, source passage(s), and source count |
| **Supported grades** | 8–10 |
| **Rubric** | Project rubric adapted from the Carnegie Foundation / ETS Skills Progressions, informed by the SFF critical-thinking framework |
The evaluator was built and validated using the model below (other configurations, including cheaper models, produced lower and less stable agreement — see [Validation and limitations](#validation-and-limitations)):
| | |
| :-------------- | :------------------------------------------------------- |
| **Model used** | Claude Opus 5, version-pinned (`claude-opus-5-20260723`) |
| **Temperature** | Not configurable — Opus 5 accepts no sampling parameters |
## Getting started
Follow the [Quickstart](/evaluators/getting-started/quickstart) to start using this evaluator:
| Access method | |
| :------------------------ | :--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Evaluators playground** | [View in Platform](https://platform.learningcommons.org/apps/evaluators/playground) ↗ |
| **SDK** | Not yet available (v0.1, early access) |
| **GitHub** | [Python notebook](https://github.com/learning-commons-org/evaluators/blob/main/evals/critical-thinking/argumentative-essay/example_notebook.ipynb) ↗
Prompts ([`system.txt`](https://github.com/learning-commons-org/evaluators/blob/main/evals/critical-thinking/argumentative-essay/system.txt) ↗ and [`user.txt`](https://github.com/learning-commons-org/evaluators/blob/main/evals/critical-thinking/argumentative-essay/user.txt) ↗)
Schemas ([`input_schema.json`](https://github.com/learning-commons-org/evaluators/blob/main/evals/critical-thinking/argumentative-essay/input_schema.json) ↗ and [`output_schema.json`](https://github.com/learning-commons-org/evaluators/blob/main/evals/critical-thinking/argumentative-essay/output_schema.json) ↗) |
## Inputs
| Input | Description | Required |
| :-------------------- | :------------------------------------------------------------------------------------------------------- | :------- |
| **Assignment text** | Writing prompt the student answered | Yes |
| **Source passage(s)** | Source passage(s) shown to the student | Yes |
| **Source count** | Number of source passages provided (rates "Synthesizing sources" only when there is more than 1 passage) | Yes |
| **Essay text** | Student essay (200–800 words recommended) | Yes |
## Output
| Field | Description |
| :---------------------- | :---------------------------------------------------------------------------------------------------------------------------------- |
| **Indicators** | One entry per rated indicator — Synthesizing sources, Evidence strength, Counterarguments, Facts over opinions, Drawing conclusions |
| **Indicator evidence** | Verbatim quote(s) from the essay per indicator, each with a short comment on what it demonstrates |
| **Indicator reasoning** | Reasoning for the rating, written before the rating itself |
| **Indicator rating** | 5-level scale: Not Evident, Exploring, Analyzing, Integrating, Extending |
| **Overall reasoning** | Reasoning including the median arithmetic across the indicator ratings |
| **Overall rating** | Headline Critical Thinking rating, same five-level scale |
## Interpreting results
| Output | How to use |
| :---------------------------------------- | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Indicator rating + evidence/reasoning** | Formative signal on where an essay sits on a specific critical-thinking skill
**Example**: Flag essays that rate low on Counterarguments or Facts over opinions for targeted instruction; show the quotes so a teacher can check the rating |
| **Overall rating** | Cohort- or portfolio-level signal on critical thinking, distinct from writing quality
**Example**: Research or program-level analysis of critical-thinking trends across a set of essays, rather than an individual grade |
## Evaluator release history
| Date | Changed |
| ----------------- | ------------- |
| September 3, 2026 | First release |
## Related topics
Explore evaluators that rate student work against a construct's indicators.
Run an evaluator in the Evaluators playground, a Python notebook, or with
the SDK.