A 21-Day Habit Formation Intervention Based on Self-Determination Theory: Dual Promotion of Behavior Improvement and Mental Health in Vocational High School Students

Objective: The habits of vocational high school students in terms of sleep, reading, and exercise are not optimistic, and there is a serious dependence on mobile phones. Based on Self-Determination Theory (SDT), this study designed a 21-day habit formation experiment to help students develop good habits through intervention. Results: A total of 138 vocational high school students from our school were selected as research subjects and divided into four groups: early sleep habit, reading habit, exercise habit, and skill formation. Through continuous completion of corresponding habit goals for 21 days and daily check-ins on WeChat, the following results were found:Quantitative results are as follows: (1) Mental health was promoted: The self-efficacy of all participants was significantly improved (from 28.94 to 31.86); (2) Habit behaviors were improved: Paired sample t-tests showed that the early sleep group had significant improvements in sleep schedules before and after the activity, the reading group had a significant increase in the number of days of active reading, the exercise group had a significant increase in the number of exercise days, and the time spent watching short videos on mobile phones was significantly reduced; (3) 91.3% of students persisted in completing the 21-day target habit behaviors, and 80% of students were very satisfied with the activity.Qualitative results are as follows: Students who participated in the activity believed that: (1) Through persistence, they experienced the most intuitive improvements and enhancements in sleep, reading, exercise, and skill formation; (2) The activity improved students' self-discipline; (3) The habit formation activity greatly enhanced self-management abilities.Conclusion: Habit formation activities can promote the development of good habit behaviors, reduce bad habit behaviors, and improve students' mental health levels.