Luke unexpectedly finds his broken toaster at the diner has been fixed. (He was shown trying to mend it himself when Mia arrived, so it was out of action for nearly a week). Jess denies that he had anything to do with it, but Rory gives him an approving smile as he leaves for school.
Jess’ actions symbolise that he is capable of working to fix his relationship with Luke, just as Luke mended and waterproofed Lorelai’s chuppah. It’s yet another scene where Jess is depicted as the mirror image of Luke, and shows he is also good at practical things – he’s not just book smart.
There’s nothing like the thrill of reforming a bad boy, so no wonder Rory looked so pleased with herself. Jess is very careful to look back at her to watch her reaction as well. It’s something else he’s done to make an impression on Rory, and it feels like another piece of his plan falling into place.