PURPOSE: A number line consisting of Arabic numerals is a commonly used instructional tool for teaching price comparison. However, typical number lines lack concrete visual cues, which may benefit students with autism spectrum disorders (ASD) who have not yet mastered the representation of Arabic numerals.
METHOD: This study investigated the effects of additional visual cues (i.e., dots) by comparing two types of app-based number line conditions: number lines with and without dots. A single-subject, alternating treatment design study was employed across five secondary students with ASD.
RESULTS: Both number line conditions were effective for four of the students in assisting them to select cheaper items and complete task analysis steps. The number line with dots was effective or slightly more effective in selecting smaller numbers for three of the students.
CONCLUSIONS: The findings of this study support the literature on the use of number lines as an effective tool to assist students in price comparison. The benefits of adding concrete visual cues and other teaching strategies (e.g., the holistic and decomposition models) were discussed. Implications for Rehabilitation This study investigated the effectiveness of concrete visual cues, such as dots, on a number line app for teaching students with ASD who had not yet developed the association of quantities with the numerals. We found that incorporation of a hybrid number comparison model - first holistic (for whole numbers) and then decomposition (for numbers after the decimal point) - is effective when teaching students how to compare prices with an uneven number of digits. This study provides an alternative for special education teachers to schedule practice, such as the use of simulated settings to achieve mastery, then transitioning to community-based settings to test skill generalization.