He bursts in - well, the door was open, but his arrival tends to be of such enthusiasm that it still makes the turn of phrase seem worthwhile.
"Sorry I'm late, I ran home to get some books for Fornax. I took some of the ones that Gawain doesn't read any more. I'll get him new ones..."
Showing off his haul - much loved, likely belonging to the entire Anderson crew before making it to the youngest. The Very Hungry Caterpillar, Brown Bear What do you See, Fox in Socks, and...