How Teachers of the Visually Impaired Compensate with the Absence of Accessible Block-Based Languages
Aboubakar Mountapmbeme, Stephanie Ludi · 2021 · Proceedings of the 23rd International ACM SIGACCESS Conference on Computers and Accessibility (ASSETS '21) · doi:10.1145/3441852.3471221
Summary
This paper reports on an interview study with twelve teachers of K-12 students with visual impairments (TVIs) across the United States, investigating how they navigate the lack of fully accessible block-based programming environments. Block-based programming languages like Scratch have become the standard entry point for teaching coding to young students, yet most mainstream block-based environments remain inaccessible to students with visual impairments. The study addresses two research questions: what causes the accessibility challenges previously reported in the literature, and what do teachers use in the absence of accessible block-based languages. The researchers conducted semi-structured interviews via Zoom, using thematic analysis with affinity diagramming to identify 28 codes organised into 9 high-level themes. The participants ranged from 4.5 to 30 years of teaching experience and taught grades from K through 12. The study catalogued the programming environments teachers actually use, including Blocks4All, Scratch, Swift Playgrounds, CodeQuest, Edison, Quorum, Code.org, Code Jumper, CodeSnaps, and Snap Circuits. Of these, only Blocks4All and Swift Playgrounds were identified as accessible on-screen environments, with Quorum being the primary accessible text-based alternative. The COVID-19 pandemic emerged as a significant factor, forcing teachers to abandon tangible and physical programming activities in favour of on-screen alternatives, further highlighting the need for accessible block-based environments.
Key findings
The study identified three major factors contributing to accessibility challenges. First, students' limited prior exposure to basic computing skills — particularly screen reader proficiency, keyboarding, and touch screen interactions — significantly slows the learning process. Teachers reported spending considerable time teaching tool skills before they could begin teaching programming concepts. Second, teachers' own limited CS backgrounds created barriers; some TVIs assigned to teach coding lacked programming knowledge, preventing them from considering accessible alternatives like the Quorum language. Third, existing curricula and lesson plans were either too limited or too complex for students with visual impairments, with teachers having to personally modify materials by introducing scaffolding activities and providing alternate instructions. To compensate for inaccessible block-based environments, teachers employed three main strategies: using tangible programming toolkits like Code Jumper and CodeSnaps as physical alternatives; preferring robotic and haptic activities that provide accessible auditory and tactile feedback; and defaulting to Swift Playgrounds as the only accessible hybrid block/text environment. Swift Playgrounds was chosen primarily because it integrates with VoiceOver, includes tactile maps, and runs on iPads students already know. However, teachers reported that editing programs on Swift Playgrounds remains difficult, particularly for blind students who struggle with adding or deleting characters using the VoiceOver rotor.
Relevance
This study reveals a significant gap in the accessible computing education pipeline: while researchers have created a few accessible block-based environments, these tools have not reached widespread classroom adoption. For accessibility practitioners and tool developers, the findings highlight that accessible programming environments must address not only technical accessibility but also the broader ecosystem of teacher training, prerequisite student skills, and curriculum design. The emphasis on orientation and mobility skills as a precursor to understanding spatial programming concepts (like moving an avatar on a grid) suggests that accessible programming environments should offer non-spatial alternatives or embodied learning approaches. The practical workarounds teachers have developed — using physical robots for tactile feedback, having students act out code with their bodies, placing plastic cups along robot paths for auditory feedback — offer valuable design insights for creating more accessible programming tools. The study also underscores the urgency of developing fully accessible on-screen block-based environments that work with screen readers, given that remote learning situations make tangible alternatives impractical.
Tags: visual impairment · block-based programming · K-12 education · computer science education · accessible programming · teachers of the visually impaired · assistive technology · screen readers
Standards referenced: VoiceOver