Mastering Both Math and Space with the Cosmic Number Lines App

An accessible, engaging iOS game, the Cosmic Number Lines App was designed for early elementary school students who are blind or low vision. Students take the role of astronaut-in-training on the distant planet Sileni. Through a series of space adventures and problems designed to develop number line concepts and skills, students take their character from the rank of trainee to captain. The game has been created to help students develop foundational math skills such as constructing number lines, locating points, comparing numbers, solving addition and subtraction problems, and counting units to find distances.
Accessible Features
The Cosmic Number Lines App also features the Split Tap gesture, which allows students to explore elements on the screen with one finger, while activating the elements by tapping anywhere with another. “Unlike the commonly used double-tap gesture in VoiceOver, which requires users to lift and tap with the same finger, the split tap allows users to keep the first finger on the desired element while tapping with a second finger to activate it. This can make interaction more spatially informative,” said Product Manager Li Zhou. “The double-tap gesture often results in jumping from item to item without understanding their physical arrangement on the screen. This makes it difficult to develop a clear mental model of the number line. The split tap gesture, by contrast, supports spatial awareness and offers a more effective way for students to engage with the content.”
Alongside unique sound cues, the Cosmic Number Lines App has been created with intentional features to serve students as they develop number line concepts. The game includes eight progressively structured levels covering fundamental concepts and skills related to number lines. Problems throughout the game become increasingly challenging, encouraging both mastery of skills as well as creative problem solving. Each time the Level 8 activities are opened, the numbers will randomize, allowing students to play multiple times with new challenges. Activities in each level are divided into either training or tasks. The story line has been equipped with guided training sessions before new tasks begin to help students build understanding step-by-step to create a solid foundation of knowledge before moving to more difficult problems. All training activities must be completed before moving onto the tasks for each level.
Collaboration in the Classroom
The app can be used on any iPad or iPhone as a mobile game for independent learning and is a great supplement to classroom instruction from all students, regardless of vision level. The game has been made with vibrant visuals that both capture student attention and boost motivation. Field testing with teachers showed that students with low vision especially loved the designs of characters, as well as the engaging sound effects. Giving students the capability of playing simultaneously with sighted peers, makes the app a classroom tool to encourage classroom collaboration across vision levels. With full accessibility support, it can be played by students who use screen readers and/or braille displays.
Made for early elementary school students, specifically grades 2 and 3, the Cosmic Number Lines App is designed to help continue learning and mastery of number line concepts. Students will also practice foundational math skills such as finding the distance between points, solving addition problems, and solving subtraction problems. “Learning through gameplay is an effective approach for all students, including those who are blind or low vision. However, there has been a lack of educational apps that are accessible to students who are blind or low vision. This app helps address that gap. With enlarged elements, high-contrast colors, carefully selected gestures, and full support for iOS’s screen reader, VoiceOver, its accessibility features make it uniquely valuable compared to other similar apps,” said Zhou. The Cosmic Number Lines App is expected to be released early summer of 2025 and will be available in the iOS app store.
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