The group, from Durrington High, headed to the Nuts Challenge course, in Dorking, as part of the school's strategy to promote positive well-being and mental health through physical activity.
With this year's GCSE exams looming, it also gave the Year 11 students and their teachers the chance to have some fun.
A school spokesman said: " The sheer volume of mud, having to get in and out of rivers and climb a range of obstacles made the day absolutely fantastic to be part of. We plan to organise many more events like this now!"
As part of the challenge, Durrington High is raising money for the Samaritans.
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