We found a fun family activity to do while on Kauai - boogie boarding! The only things you need are a boogie board and some waves. The best place to rent a boogie board is at the Hanelai Activity Center. Cost is $5 for 24 hours.
The best place we found to boogie board was Hanalei Bay Beach. This is a great place for all ages. Several surfing schools conduct their instructions in this bay. The water is perfect and the sand bottom is soft, so you do not have to worry about lava rocks cutting your feet. It’s a great activity for all ages!!!