She further said that about 1/3 of the kids in her practice have ADHD and are being home-schooled.
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I am willing to bet that they were not homeschooled from the beginning.
All children are home-schooled from the beginning. When a parent brings a 2, 3, or 4 year old to the doctor with attentional concerns, the parent is the concerned 'teacher' not the public schools.