Cheerleader Casey (S03E23)

S03E01 Two Timing Derek S03E02 It's Our Party S03E03 Misadventures In Babysitting S03E04 Slacker Mom S03E05 Power Failure S03E06 Don't Take A Tip From Me S03E07 The Bully Brothers S03E08 Home Movies S03E09 Show-Off-Tune S03E10 Summer School Blues S03E11 Grade A Cheater S03E12 Adios Derek S03E13 Fright Night S03E14 Sixteen Sparkplugs S03E15 When Derek Met Sally S03E16 A Very Derekus Christmas S03E17 Ivanwho? S03E18 Rumor Mill S03E19 Derek Un-Done S03E20 Not So Sweet 16 S03E21 Driving Lessons S03E22 Make No Prom-ises S03E23 Cheerleader Casey S03E24 Allergy Season S03E25 Things That Go Bump In The Night S03E26 Derek's School of Dating