The mood was influenced by many factors in children. Sport, such as high-altitude mountain trek activity was thought benefit for human's mood and health. The expedition therapy was more and more popular in many schools recently. However, as the investigators best knowledge, there was no article discuss the relation between the mood and high-altitude mountain trek activity such as benefit influence in children. So, the investigators conduct the study.

Method: Demographic data will be recorded. The Professor Yeh's mood questionnaires were used to record the mood status of before and after the 3 days high-altitude mountain trek activity.

Statistical analyses: Participants rated their emotional states (happiness, sadness, anticipation, and anger) on a Likert scale. Each variable will be presented as descriptive statistics. Student t test or other suitable statistical method(s) will be used to determine the correction among the variables with scores of mood status. The paired t test or other suitable statistical method(s) will be used to determine the correction among the scores of mood status before and after the mountain activity. A difference was considered statistically significant if the p value were less than 0.05. All statistical analyses will be performed using SPPS statistical software for Windows, version 14 or more updated version.

Inclusion Criteria:

• Sixth-grade elementary students who participated in a 3-day, 2-night high-altitude mountain walking trek from the trailhead (2,140 m above sea level) to the summit of Xue Mountain (3,886 m above sea level)
• Subject who provide the written informed consent from participants and their legal guardians before the distribution of the questionnaires.

Exclusion Criteria:

• Not Sixth-grade elementary students.
• Not finish the 3-day, 2-night high-altitude mountain walking trek from the trailhead (2,140 m above sea level) to the summit of Xue Mountain (3,886 m above sea level)
• Subject who do not provide the written informed consent from participants and their legal guardians before the distribution of the questionnaires.

Sixth-grade elementary students who participated in a 3-day, 2-night high-altitude mountain walking trek from the trailhead (2,140 m above sea level) to the summit of Xue Mountain (3,886 m above sea level).