> ## 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.

# Literacy

> Access and understand the literacy dataset used for evaluator development, including expert-annotated benchmark data for text complexity evaluation.

<EarlyAccess isBreaking={false} />

<Note>
  [Look at the annotated
  data.](https://github.com/learning-commons-org/evaluators/tree/main/datasets) ↗
</Note>

## About the dataset

The Literacy dataset contains high-quality text complexity annotations for the CommonLit Ease of Readability (CLEAR) Corpus by literacy and education experts.

The <Tooltip tip="CommonLit Ease of Readability">CLEAR</Tooltip> Corpus was produced by [CommonLit in collaboration with Georgia State University](https://www.commonlit.org/blog/introducing-the-clear-corpus-an-open-dataset-to-advance-research-28ff8cfea84a/) ↗ and released in December 2021. It comprises nearly 5000 publicly available excerpts, each mapped against dimensions including Flesch-Kincaid and <Tooltip tip="Bradley-Terry">BT</Tooltip> Easiness (Bradley-Terry coefficient based on teacher ratings of the text). We expanded the dataset by scoring a subset of rows for dimensions in Student Achievement Partners (<Tooltip tip="Student Achievement Partners">SAP</Tooltip>)'s [Qualitative Text Complexity Rubric for Informational Text](https://learnwithsap.b-cdn.net/app/uploads/2026/04/Qualitative-Text-Complexity-Rubric-Informational.pdf) ↗.

Our [Literacy evaluators](/evaluators/literacy-evaluators/introduction) use this dataset as a benchmark when assessing AI-generated content. We hope edtech developers can use it to complement their own literacy work as well.

<Note>
  Our initial release in September 2025 focuses on Grades 3 and 4 across
  sentence structure and vocabulary, but we plan to expand to all grades and all
  dimensions of text complexity assessed through{" "}
  <Tooltip tip="Student Achievement Partners">SAP</Tooltip>'s Qualitative Text
  Complexity rubric.
</Note>

## Our process

Our process for producing annotated data is as follows:

* Filter the <Tooltip tip="CommonLit Ease of Readability">CLEAR</Tooltip> corpus to an approximate grade 3-4 range using Flesch Kincaid Grade Level.
* Partner with literacy experts from <Tooltip tip="Student Achievement Partners">SAP</Tooltip> and Achievement Network (<Tooltip tip="Achievement Network">ANet</Tooltip>) to score against dimensions in SAP's Rubric.
* With SAP and ANet, establish a gold set of \~80 examples per grade with representation across the 4 tiers of text complexity (Slightly, Moderately, Very, and Exceedingly complex)
* Use the gold set to test and qualify a cohort of educators with 2+ years of experience teaching English Language Arts (<Tooltip tip="English Language Arts">ELA</Tooltip>) at the corresponding grade level.
* Produce 200+ rows (50+ per complexity tier), calibrating annotator scores using the Dawid-Skene method.

<Frame>
  <img
    src="https://mintcdn.com/czi-60a2a443/bb-F2r75Gz83PPsi/images/evaluators/our-annotation-process_flowchart.svg?fit=max&auto=format&n=bb-F2r75Gz83PPsi&q=85&s=051e642ca35a5cf1a05ad7093539e268"
    alt="flowchart showing a high-level overview of the annotation
process"
    width="1392"
    height="496"
    data-path="images/evaluators/our-annotation-process_flowchart.svg"
  />
</Frame>

Finally, we package the dataset by mapping multiple dimensions of text complexity to the clear\_id column. This results in an annotated dataset that can be easily merged with the <Tooltip tip="CommonLit Ease of Readability">CLEAR</Tooltip> corpus.

## Columns

<Note>
  Last updated September 23, 2025

  This list will be updated as we incorporate more text complexity dimensions.
</Note>

| Column                              | Definition                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| :---------------------------------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **UID**                             | Unique identifier for each row.                                                                                                                                                                                                                                                                                                                                                                                                                          |
| **Clear ID**                        | Identifier for texts based on the <Tooltip tip="CommonLit Ease of Readability">CLEAR</Tooltip> corpus. This is not a unique identifier, as some texts were scored for multiple grades.                                                                                                                                                                                                                                                                   |
| **Grade**                           | Grade-level for which the text is scored. For example, if Grade=3 and Sentence Structure Complexity Score Slightly Complex, then the text is Slightly Complex for a third-grade student (see overall project documentation for specific assumptions).                                                                                                                                                                                                    |
| **Flesch-Kincaid**                  | Flesch-Kincaid Grade Level score for the text, provided from the <Tooltip tip="CommonLit Ease of Readability">CLEAR</Tooltip> corpus.                                                                                                                                                                                                                                                                                                                    |
| **Text**                            | Text from the <Tooltip tip="CommonLit Ease of Readability">CLEAR</Tooltip> corpus that was annotated.                                                                                                                                                                                                                                                                                                                                                    |
| **Sentence Score**                  | Overall annotator rating for sentence structure complexity. Takes the values slightly complex, moderately complex, very complex, and exceedingly complex. See the technical docs for additional details on these categories.                                                                                                                                                                                                                             |
| **Sentence Score Rationale**        | Annotators’ explanations for their sentence structure score.                                                                                                                                                                                                                                                                                                                                                                                             |
| **Vocabulary Score**                | Overall annotator rating for vocabulary complexity. Takes the values slightly complex, moderately complex, very complex, and exceedingly complex. See overall project documentation for additional details on these categories.                                                                                                                                                                                                                          |
| **Vocabulary Score Rationale**      | Annotators’ explanations for their vocabulary score.                                                                                                                                                                                                                                                                                                                                                                                                     |
| **Tier 2 Words**                    | Words that are commonly used in academic settings and are more complex than colloquial, or everyday language, and often have multiple meanings<br /><br />**Example:** "There are eight planets in the Solar System. From closest to farthest from the Sun, they are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune." Most planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune) are Tier 2 words for Grade 3. |
| **Tier 3 Words**                    | Words that are limited to a specific domain or that are so rare that an avid reader would likely not encounter them in a lifetime<br /><br />**Domain-specific example:** enzyme <br />**Rare unconventional example:** abecedarian                                                                                                                                                                                                                      |
| **Archaic Words**                   | Words, or uses of words that are not commonly used in modern conversational language<br /><br />**Example**: "The jury retired to deliberate on their verdict." Using "retire" to mean "withdrawing to a private place" is an archaic use.                                                                                                                                                                                                               |
| **Other Complex Words**             | Additional complex words for students of the grade level, as identified by annotators.                                                                                                                                                                                                                                                                                                                                                                   |
| **Background Knowledge Assumption** | LLM-generated information on the background knowledge that students of a particular grade are likely to have about a topic. Information was provided to annotators during the scoring process. See the overall project documentation for detailed methodology on how this was generated.                                                                                                                                                                 |

<Note>
  Receiving **Not Scored** for a given column means that the text was not
  annotated for that column.
</Note>

## Limitations

* Annotator coverage per item is limited; reported precision and agreement reflect this coverage.
  * Annotations in future updates will improve statistical reliability by increasing confidence, reducing variance, and stabilizing borderline cases.
* Flesch–Kincaid grade estimates (based on sentence and word length) are heuristic and do not capture qualitative factors (e.g., conceptual difficulty, vocabulary sophistication, thematic maturity).
  * They are recorded as metadata and may be referenced in the evaluator prompt as one of multiple signals.
  * They are not the sole determinant of evaluator labels.
