'The Practice Kiss'

Because Keith is a clueless dolt who really actually though the kiss was for practice. Watts was basically desperate to have Keith touch her the way she wanted him to. So she proposed this scenario where she could have her cake and eat it too. Unfortunately for her, it was torture more than anything else, because in the end it was Amanda that Keith was thinking about at the time; Amanda was the one he was practicing for. So, in self preservation, before she let slip her true feelings, she pushed him away in an attempt to cover all that up. He thought she was just embarrassed, inexperience, and was suffering from a bit of self-doubt. What she was actually feeling was:
"OMG, did he actually see and could feel how I felt about him in that
kiss? Does he know how much my helping him get the girl he really
wants is tearing me up inside?"
I think as a teenage girl, to have a guy who doesn't think of you in those terms know you're in love with him is akin to dying a slow humiliating death.

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I missed that part when Watts said something like "...the day I ever blush!" (as she's resembling a Coke can). Great scene, more-so when she told him to grow up.