'The kings of giveback'

The enduring greeting card image of Father's Day is of a dad brandishing a set of tongs over a smoking barbecue grill.

These days, a more realistic image would be of a dad sporting a baseball cap and whistle, clutching a clipboard filled with lists of names, play diagrams and game statistics. Or, chauffeuring a budding athlete to a faraway practice or game, and staying on to cheer, fill up the water cooler and hand out high fives.

The soaring popularity of youth sports finds many dads juggling work schedules in order to direct practice drills or plot the lineup for next season's youth league sports teams. These unpaid...