There was a student named Eliza A. T. Blake at the Mordecai school when it first opened--she was there from 1809 till the end of 1810. She's listed as being from Petersburg VA, and has an Ellis G. Blake listed as the adult on her account.
An Ellis Gray Blake (1768-1816) of Boston MA married Mary "Polly" Taylor (c1773-1811), daughter of Col. Henry Taylor of Southampton County, Virginia. They had a son Henry Taylor Blake (1798-1866), who became a merchant, a son Bennett Taylor Blake (1800-1882), a clergyman who founded the Greensboro Female College and another girls' school in Raleigh; a son Ellis Gray Blake (1802-1863), who became a medical doctor and a teacher; a son Nathaniel Oliver Blake (1804-1880), also a clergyman.
Did they also have a daughter Eliza, about the same age as these four sons? Ellis's older sister Elizabeth Blake died in 1801; a daughter born around that time might well have been named for her, and the T would be for Taylor (the same middle name that two of the sons have). If so, she's not listed in this 1898 Blake genealogy along with the others. But daughters are often left out of such works, especially if they don't live to adulthood, marry or have notable sons.
If this is the family of Mordecai student Eliza A. T. Blake, she has a rather infamous connection on her mother's side. Polly Taylor's sister Elizabeth Taylor married Peter Blow of Southampton VA in 1800. And Peter Blow was the first owner of Dred Scott. Peter Blow's son (Eliza's first cousin?) Henry Taylor Blow (1817-1875) was a Congressman from Missouri, and served the Lincoln administration as ambassador to Venezuela (1861-1862), and the Grant administration as ambassador to Brazil (1869-1870). And Henry's daughter Susan Elizabeth Blow (1843-1916) was founder of the first kindergarten in St. Louis.
Were these Eliza A. T. Blake's relatives? If so, did she live to see any of these events? Or is her time at the Mordecai school her only mark on the historical record?
UPDATE (11.1.10): I realized that I had more information about Eliza A. T. Blake in another appendix of my dissertation. "After leaving the school... Eliza continued contact with the family, visiting in 1813, and welcoming [Ellen Mordecai] to Petersburg in 1817. By that later event, she was Mrs. Willcox. She and another Mordecai alumna, Susan King Moss, ...made plans to attend the examination at the Plunkett school in 1822."
The Willcox connection is the key. In a Blake genealogy published 1898, we find Eliza Ann Taylor Blake Willcox (1795-1825), who was indeed the daughter of Ellis Blake and Mary Taylor, and the elder sister of Henry, Bennett, Ellis, John and Nathaniel Blake. Eliza A. T. Blake, then, was fourteen when she arrived at the Mordecai school; at 16, she lost her mother, and was probably called home to help around that event. She married in 1815, so she was twenty that year. The next year, her father died. Eliza herself died in 1825, age 30. No evidence of children, and the answer is, no, she didn't live to see any of the events affecting her maternal relatives, as outlined above.