This study examined how short-video characteristics influence attention and time perception in high school students. Building on prior findings that playback speed, color tone, and emotional content are key factors, we conducted a time discrimination experiment with 35 female participants, measuring accuracy and reaction time under varied video conditions. In addition, a survey of 265 students explored relationships among time management habits, time perception, and short-video usage. Results showed that color tone significantly affected task accuracy, while both speed and color tone significantly influenced reaction time. Slower playback (0.75×) led to faster responses than higher speeds (1.25× and 1.75×), and chromatic videos—especially blue and green—produced shorter reaction times than achromatic ones. These findings suggest practical implications for designing digital educational content that optimizes visual presentation and sustains attention. Survey results further revealed that frequent short-video viewers perceived time as passing faster and exhibited reduced accuracy in time estimation, indicating potential negative effects on temporal perception that warrant further investigation.