I have three girls with the surname "Bott" in the rolls of the Mordecai school:
Catharine Bott attended the school during 1816 (both sessions), with Miles Bott as the adult name attached to her account.
Lucy J. Bott of Mansfield, Amelia Co., VA also attended the school during 1816 (both sessions, with James Bott as the adult name on the account.
Martha Bott attended the school for three sessions (from mid-1815 to the end of 1816), with Miles Bott as the name attached to the account.
So all three Bott girls were at the school together for the two sessions of 1816. Probably not a coincidence--it was common to send sisters and cousins to school together. And there were a lot of Botts in Virginia, including several generations of Miles Botts. A Miles Bott served on the Virginia jury for the inquest into the treason charges against Aaron Burr in 1807. The Botts are much entangled with the Branch family, and we'll get to them soon in the alphabetical order.
Best I can tell, Martha Ann Bott was the daughter of Miles Bott Jr. (1762-1835) and his wife, whose surname was maybe Beverley or Broadie. She was born in 1799, and married for the first time to Samuel Parkhill in 1817, not long after attending school in Warrenton; she moved to Florida about ten years later, and married two more times, to judge Hiram Manley (1802-1853) of Tallahassee (a Harvard alum who was originally from Massachusetts), and John Johns. She may have ended up back in Virginia by the time of the third marriage. "Martha Ann Manley, late Parkhill" appears in the case notes for a Florida Supreme Court judgment in 1844, as the administratrix of her dead first husband's estate.
Lucy J. Bott was probably the daughter of James Bott and Lucy F. Branch. James Bott died in 1813, so maybe it was his estate or a son also named James who paid Lucy's school bills.
Catharine Bott doesn't turn up anywhere--except as the living British soprano of the same name--but she was likely a sister to Martha Ann?