Why did the children feel more cheerful as they toiled back up the gorge in prince Caspian?

The children felt more cheerful as they toiled back up the gorge in Prince Caspian because they had just successfully completed a challenging mission, which boosted their confidence and sense of accomplishment. Additionally, their teamwork and camaraderie during the journey created a positive and uplifting atmosphere. The shared experience of overcoming obstacles together likely strengthened their bond and contributed to their overall mood.