My 6yo DC does football after school on Mondays and swimming after school on fridays.
When he is tired he kicks off at bedtime (which is currently 6.30pm on the aforementioned days and 6.45pm on other days), he'll make ridiculous requests "I want a carrot" (we have no carrots) for example. He'll scream and cry and tantrum for up to an hour.
He is a very good boy. He only tantrums when tired, he's always needed an early bedtime, always needed lots of sleep.
DH and I are torn between keeping the activities but putting him to bed at 6pm on those days, or stopping the activities until after the winter because perhaps he is too young to handle it?