Cub Scouts do not earn badges like Boy Scouts do, but there are a number of supplemental award programs they can work on. They should focus on rank achievements first, but these programs will provide an opportunity for some extra activities.
Scouting Program Archives: National Summertime Pack Award
Hopefully your Cub Scout Pack will remain active this summer. If your Pack has one activity each month, you might qualify for the National Summertime Pack Award.