Fun in youth sport is about supporting an environment that will provide great athlete development. Fun is multi-factorial and every individual will have slightly different thoughts but some of these parts help parents and coaches make sense of how they support players.
This looks like aspects of the following:
PHYSICAL
Getting playing time and competing
Being active and working hard
Getting time on task
VERBAL
Positive feedback & encouragement
Clear communication and guided learning (rather than explicit direction)
Officials making consistent calls
EMOTIONAL
Active listening
Creating safety around learning (safe to try and fail)
Building player confidence
SOCIAL
Facilitating a supportive environment
Team rituals - such as high fives, fist bumps, hugging, cheering
Doing things outside of competition and training as a team
ENVIRONMENTAL
Well organised practices that are age and stage appropriate and include games
Good facility conditions
Competing against evenly matched opposition