(Morgan York) is one of the many classmates of Miley, Lilly and Oliver. Known as "Saint Sarah" because of doing a lot of good deeds, like preparing food for the poor, giving money to charity, donating to the blood bank, reading to the blind, etc.

She is very kind-hearted but can get competitive and somewhat mean to people sometimes (especially Oliver). She is an environmentalist which she learned from her Dad, Woody (Ed Begley Jr.) and her Mom who met at a Red Cross event. She has a very jealous crush on Jackson and is determined to wait for him to return her feelings. An early riser, Sarah always wears glasses, and is known to have two pairs of socks, a pair and a spare. She generally leaves people by saying a cheery "Bye." She is first seen competing in the class campaign to raise money for the United People's Relief Fund. While Miley and her friends want to use the $500 mall gift certificate prize to buy stuff for themselves, they are shamed by Sarah's wish to buy clothing for the less fortunate. Deciding to help Sarah by giving her the "Hannah money," (donations Hannah personally solicits from her fans during a concert) they are disappointed to learn their rivals Amber and Ashley simply had their fathers make larger donations.

Her last name might be Armstrong because of what Rico calls her dad in "Would i lie to you Lilly?"

After Miley traps Amber and Ashley to use the prize as Sarah intended, the scheming pair also find themselves spending a day at the soup kitchen with their chipper class mate ( Money for Nothing, Guilt for Free ). When Amber and Ashley release their list ranking the coolness factor of students in their grade, Sarah regretfully snubs Miley and Lilly, the bottom two, noting that she's "charitable, not stupid." ( The Idol Side of Me ). She and Oliver are teamed together as parents for a flour sack baby. This leads to romantic feelings, developing between the couple which fade once the school project is over (My Boyfriend's Jackson and There's Gonna Be Trouble ). She accidently displays athletic skills in kicking a football while saving an ant hill, thus leaving "Stinky" Stewart the last girl picked in Gym Class again (Cuffs Will Keep Us Together). She is asked out to a school dance by her lab partner, Gabe LaMatti (You Are So Sue-able to Me ).

She develops a crush on Jackson, who was really asking her out for Rico (Song Sung Bad) . While studying World Cultures with Mr. Corelli, she creates the country of "Sarahtopia" and engages in hostile actions with Oliver's "Okenland" (Lilly's Mom Has Got It Goin' On). Still enamored with Jackson, she jumps at the offer to work at Rico' s Surf Shack. However, the changes she makes (not using cups or plates, and having her Dad, Woody, power the shack by bike pedaling) upsets Rico, who can't find it within himself to fire her. Instead he promotes Sarah to manager and agrees to her making the place more enviromentally green. Happy, Sarah can continue to keep an eye on "Her Man"--creeped-out co-worker--Jackson Stewart (Would I Lie to You, Lilly? ).