We first met Amy Madison in the second episode of Buffy's first season. Amy had been friends with Willow for awhile and "rekindled" their friendship while Buffy was trying out for the cheerleading squad. As time progresses, the cheerleaders start to exhibit sudden supernatural deformities. Upon investigating, the Slayerettes discover that these girls are being bewitched.
Buffy, Xander, and Willow figure out that Amy is the one bewitching the girls so that she can get onto the squad. Suddenly, Buffy becomes striken with a horrible fever, induced by Amy. Giles and Buffy rush to Amy's house to talk with her mother and find out that Amy's body had been taken over by her mother, who wanted to relive her glory days as a high school cheerleader. "Ms. Madison" helps the two find "Amy's" spellbook and brings it to the school, where they switch the two bodies back and expell Amy's mother into a dark void...actually, she's trapped inside the cheerleading trophy in the trophy case.
Our second run-in with Amy occured in the Valentine's day episode second season. Against her better judgement, Cordelia dumps Xander to fit in with her friends. Heart broken and a little angry, Xander goes to Amy for her help in casting a love spell. The spell works, but not on Cordelia. Every other girl is lovestruck by Xander except for her. This is a great episode where both Jenny and Amy share scenes. During one, Amy changes Buffy into a rat. With much prodding, Giles gets Amy to help him reverse the spell and change everything back to normal.
Now, we all know that most of the witchcraft we see on Buffy wouldn't be real, even to the littlest extent. But I am rather pleased with the correct representations they use. The writers had to have done at least a little homework. What can you expect from television, anyway? I don't know about you, but I hope Amy comes back in the third season!