Balloon Rockets - I've done this in several science camps I've conducted. Kids have fun with it. But, when the balloon deflates it may fall off the straw because it's surface area changes - another good thing to show and explain to kids.
Kids would love to decorate their own rings and put their names on them. When their ring lands around the roll there could be a special activity or prize. Great idea - thanks for sharing it! DIY Paper Plate Ring Toss Game - great for kids!
Best Active Indoor Activities For Kids Fun Gross Motor Games and Creative Ideas For Winter (snow days!) or for when Cabin Fever strikes Awesome Boredom Busters and Brain Breaks for high energy Toddlers, Preschool and beyond - see