The local sportsman's club would bring kids out to Crescent Lake NWR every spring for a day fishing. Unbelievable how generous these fishermen were giving up a day, using their own boats and providing tackle bait etc, as well as some prizes. We had casting contests, taught mini courses on fish species Knot tying and stuff like that. After fishing was over we dressed out some of the fish and had a shoreline fry.
Your local Wildlife Refuge would probably be anxious to host wildlife oriented events for kids or novices.