Lisa drops one of the cupcakes on the floor of the school bus...
...and then proceeds to feed Bart that cupcake.
"Hey, wait a minute. You're right.
You made me bleed my own blood!"
"Lunchtime! Haw, haw, haw!"
"Thanks Bart! We got the day off of school for this!"
"Hey, they got food at this place! Here's one for the road, dude!" (He punches Bart in the stomach)
"Oh, come on, Marge! I don't bug you when you're helping Lisa!"