I. Independent Evaluations of Homeschooling
1. In 1997, a study of 5,402 homeschool students from 1,657 families was released. It was entitled, “Strengths of Their Own: Home Schoolers Across America.” The study demonstrated that homeschoolers, on the average, out-performed their counterparts in the public schools by 30 to 37 percentile points in all subjects. A significant finding when analyzing the data for 8th graders was the evidence that homeschoolers who are homeschooled two or more years score substantially higher than students who have been homeschooled one year or less. The new homeschoolers were scoring on the average in the 59th percentile compared to students homeschooled the last two or more years who scored between 86th and 92nd percentile. ...
...4. In Nevada, according to Washoe County School District’s data, homeschooled students scored higher than their public school counterparts in first through seventh grade. All children were tested with the Stanford Achievement Test, and homeschoolers consistently scored higher in reading, vocabulary, reading comprehension, math concepts, math comprehension, math and math concepts and application.
The most extreme gap between the public school children and the homeschooled children was in the area of vocabulary. For example, fourth graders in public school scored in the 49th percentile while the homeschooled fourth graders scored in the 80th percentile. ...
http://www.hslda.org/docs/nche/000010/200410250.asp
Then Mrs. Marple should STFU.