I finished up my latest group of fly fishing merit badge scouts on Saturday. We threw, buggers,nymphs,wooley worms, poppers, ants, spiders, jitterbees.. The gills would make a wake from 6' away to inspect but not take. In an hour and a half 4 scouts and myself only caught three keepers and except for freezer filets we would not have had enough to complete the meal portion of the merit badge. I've never seen gills so selective.Any thoughts? FYI ice has been out for two weeks. Water still cold ,but it was too nice Saturday to waste the day not fishing. Thanks