 Ben Rigley, a student at aberystwyth University, reflected: "Dangling on the end of a rope inside an 80ft crevasse - not how I expected to be spending my summer." Other members of the British Schools Exploring Society (BSES), a youth development charity based in London, have noosed caiman in the amazon, watched for polar bears at night, or kayaked down the Zanskar Gorge - none of sorts of activities you'd expect to be doing at 18 and away from home for the first time.  Gap-year experiences are valued not only by gappers, but by universities and employers too. "They provide life skills such as teamwork, leadership and self-awareness that give young people real confidence in their abilities," says Dr Ceri Lewis, NERC research fellow at the University of Exeter. But with tuition fees rising and the scramble for university places increasingly fierce, round-the-world trips and island-hopping odysseys are starting to sit less comfortably with paying parents, forcing disappointed school leavers to reconsider.  The BSES thinks it has a solution: it has invited today's teenagers to consider remodelling, rather than doing away with, their gap-year dreams. Joining month-long expeditions to jungle, polar and mountain wildernesses, BSES members condense their gap-experiences into five worthwhile weeks, sandwiched between finishing their a-levels and starting university. "With conservation research embedded into each expedition, young explorers have the opportunity not only to go somewhere truly remarkable, but also to do something of value while they are there," explains Peter Pearson, BSES's executive director.  My first experience of a BSES expedition was as a science leader. Seventy-eight degrees north, I was in arctic Svalbard, a Norwegian archipelago where mirror-like fjords reflect flat-topped mountains, and crystal glaciers lick through sweeping valleys. My team of 10 youths were investigating evidence of climate change, measuring the vertical ablation of glaciers in Spitsbergen, Svalbard's largest island.  With not a day of prior polar experience between them, my group spent their first week gaining vital arctic survival skills. Under the guidance of chief mountain leader Neil Gwynne they learnt how to rescue a team-mate from a crevasse fall, ward off polar bears and make freeze-dried beef and powdered rice pudding more appetising.  Survival-skill proficient, we trekked past antlered caribou and arctic foxes into frozen mountains to begin our glaciology research. But we quickly ran, or hiked, into a problem: the glacier we wanted to measure was missing. after double-checking our GPS systems and matching the iced land forms that rose around us to the contours rippling across our maps, we gazed at the grey mound of moraine where, according to the Ordinance Survey, a 600m-wide glacier should have been. We stood staring climate change right in the snout and listening to it trickle through the glacial debris beneath us.  Our final week was spent trekking across the Lomonosov ice cap, en-route to a 1,000m peak the team was intent on reaching. We journeyed across the ice, somewhere between Norway and the North Pole, and while we'd become pretty slick at glacier-crossing, progress is slow when you're carrying your bedroom, kitchen and - in compliance with Svalbard's laws on polar-bear safety - a 5kg aK47. When a storm began to blow and we lost sight of our peak, I refuelled on a frozen  