Some ideas:

Dip net
Binoculars
Mesh bug cage
Compass
Inexpensive or hand-me-down camera
"Field" notebook and pen/pencil
Sketch book and colored pencils
Kid-friendly guide to birds/bird calls
Magnifying glass
Rain gauge
Cargo vest
Rock tumbler?
Chalk, bubbles, frisbee, hula hoop, jump rope

The days of the pocket knife are behind us. What trinkets would you get DS to help him explore this summer? He'll be outdoors a lot, so I was thinking a compass or some binoculars? Amazon has a Bug Watch that looks like fun. I'd like some ideas about items I can stick in his backpack that'll give him a sense of adventure. Please help.

Thanks!