Scoutbook can be used to keep track of who attended events.

Certain leaders have the ability to keep attendance:
Adults: Troop Admins (capability in Scoutbook)
Scouts: SPL’s, ASPL’s, Troop Guides, Scribes, and Webmasters
If you have the capability to take attendance for an event, you’ll see a box in the lower right corner:

Click it and it will change to a gold box that says Save:

Clicking on Benson turns off the gold star that means he attended:

Click on him again turns it back on:
