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PIE Framework

Open Source Assessment Items

A modern, open-source framework for assessment item rendering that combines the interactive richness of commercial platforms with the flexibility of open standards. Built on Web Components and distributed as framework-agnostic custom elements.

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Why PIE

Today's assessments demand interactive question types — graphing, drag-and-drop, mathematical expression input — delivered accessibly through browsers to millions of students. Organizations building assessment platforms face a difficult choice.

The Challenge

Commercial Platforms

Comprehensive solutions but with significant per-student licensing costs and limited customization.

Standards Alone (QTI)

QTI defines an exchange format; each platform supplies its own rendering and authoring.

Build from Scratch

Complete control but years of development to cover the range of content types with production quality and accessibility.

The PIE Solution

Open Source & Free

MIT licensed, with no per-student fees, and full source access and modification rights. Optional calculator and cloud read-aloud providers carry their own terms.

Modern & Interactive

31 element types, 30 of them with WYSIWYG authoring views, composable players and an assessment toolkit.

Enterprise Proven

PIE powers assessment delivery at enterprise scale, serving hundreds of millions of student interactions annually across approximately 40% of U.S. schools.

A two-by-two grid running from proprietary to open and from build-it-yourself to ready-made. Commercial platforms are proprietary and ready-made, building from scratch is proprietary work you do yourself, standards alone (QTI) are open but leave rendering to each platform, and PIE is open and ready-made.

What PIE Provides

Elements, players and tools for delivering and authoring interactive assessments

Secure Delivery for High Stakes

Each element's controller turns the stored model into a view model for the current mode and role. By default the controllers run in the browser, which suits practice and formative use. A hosted player loads elements without their controllers and renders models your server has processed; with answer keys stripped from those models and scores computed on your server, neither the key nor the scoring logic reaches the browser.

Graded delivery

31 Element Types

From multiple choice and inline dropdowns to graphing, charting, math entry and drag-and-drop. Each ships a delivery view and a controller; 30 ship an authoring view.

All 31 elements

Composable Players

The item player renders one item. Section players lay out a page of items and passages, with tools and accommodations from the assessment toolkit. The print player renders printable versions. Hosts assemble these into their own assessment experience; a reference assessment player shows one way to do it.

Players

Accessibility

WCAG 2.2 AA, PNP-driven accommodations, read-aloud with highlighting, sign-language alternates.

Theming

One theme element, ten accessible color schemes, font scaling, adapters for your design system.

Localization

Interface locale, content language and authored language alternates.

Timed media

Video stimuli whose playback reveals items and pauses for answers.

Security & CSP

Server-side scoring with stripped models, and the origins a strict CSP must allow.

Instrumentation

Telemetry into your own observability backend, and debugger panels for development.

Core Architecture

PIE renders and scores items in the browser, and ships server packages for read-aloud synthesis; element controllers can also run on your server for secure delivery. You bring the backend: content storage, authentication, session storage, reporting and infrastructure.

PIE Provides

  • 31 Element Types

    Multiple choice, graphing, drag-and-drop, constructed response, and more

  • WYSIWYG Authoring Interfaces

    Educators build content in visual editors, with a live preview the host renders beside them

  • Item, Section and Print Players

    The item player renders one item, section players lay out pages of items and passages with tools, and the print player renders printable versions

  • Assessment Toolkit

    Calculator, text-to-speech, accommodations, and more — coordinated through a centralized ToolkitCoordinator, around a section player or a single item player

  • QTI-Inspired Models

    Sections and assessments follow QTI 3.0's test parts, sections and item references

You Provide

  • Item Storage & Retrieval

    Your CMS, item bank, or content repository

  • Authentication & Authorization

    User management, permissions, session handling

  • Session Storage

    Durable storage for the learner sessions the players hand back

  • Assessment Shell

    Navigation, timing and submission, assembled around the players

  • Server-Side Scoring for High Stakes

    For hosted delivery: a server that runs the element controllers, strips answer keys from models and computes scores

  • Provider Accounts

    A Desmos API key and license for the default calculator, a GeoGebra license, or the bundled open-source Cortex calculator; a synthesis endpoint, /api/tts by default, for server read-aloud

  • Reporting & Analytics

    Score reports, analytics, learning insights

  • Infrastructure & Hosting

    Your servers, databases, deployment pipeline

In the browser, your application hosts the PIE players and assessment toolkit, which render the PIE elements; item config and session go in as JSON and DOM events come out. Your servers hold the item bank, sessions and scores, authentication and hosting, reached through your own API.

This separation means PIE integrates with any backend technology. Your authoring CMS and production delivery system can be unified or separate — PIE works because it speaks JSON and emits standard events.

PIE Elements: The Question Type Framework

31 element types: 26 question types plus passages, video stimulus and three rubric elements. Each element ships a delivery view and a controller. All but Match List ship an authoring view, and 12 ship a print view rendered by <pie-print>.

A section player inside your application, with a section toolbar for tools such as the color scheme, graph, periodic table, line reader and ruler. It holds item players, each with an item toolbar for read aloud, highlighting and the calculator, around a passage, a multiple-choice element and a graphing element.

Choice and text

10 elements

  • Multiple Choice
  • EBSR
  • Inline Dropdown
  • and 7 more

Math

3 elements

  • Math Inline
  • Math Templated
  • Fraction Model

Matching and ordering

7 elements

  • Match
  • Match List
  • Categorize
  • and 4 more

Graphs and images

6 elements

  • Graphing
  • Graphing Solution Set
  • Number Line
  • and 3 more

Content and scoring

5 elements

  • Passage
  • Video Stimulus
  • Rubric
  • and 2 more
Explore PIE Elements Try them live(opens in new tab)

QTI Interoperability

PIE-QTI, a sibling project, provides QTI item and assessment players for QTI 2.2 and 3.0 content (pre-1.0; certification in progress), ingests QTI 2.1, and converts between QTI and PIE.

  • Version-Agnostic Architecture — Auto-detects QTI version from XML and maps both QTI 2.x (camelCase) and QTI 3.0 (kebab-case with qti- prefix) to a shared canonical model
  • QTI Item & Assessment Players — extractors for all 21 QTI 2.2 interaction types and 78 response-processing expression kinds; coverage is broad but not yet fully conformant
  • Bidirectional Transforms — plugin-based transform packages and a CLI (in development) for converting between QTI and PIE
  • QTI 3.0 Influence on PIE — QTI 3.0 accessibility catalogs shaped the toolkit's catalog model, and its personal needs profiles follow AfA PNP 3.0, the model QTI 3.0 uses

PIE-QTI

QTI 2.2 and 3.0 item and assessment players (pre-1.0) with version detection and shared response processing, plus transforms between QTI and PIE.

QTI & Standards Docs PIE-QTI docs and examples(opens in new tab)

Trusted Partners

PIE is sponsored and developed in collaboration with leading organizations in educational technology.

Renaissance

PIE's primary sponsor and largest production user, serving approximately 40% of U.S. schools.

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MCRO

Implementation partner since 2017. MCRO has been instrumental in developing PIE from concept to production-ready framework.

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