I could be mistaken, but I though twentyten had a home.php template page included by default?
So I made my own in my child theme and it was never called. I even tried hard code
<h1>I am home.php template</h1> and it was never called with the child them activated and checked to see if it was loaded by the admin code editor and yes it was loaded, but the template still not called.
What could I be doing wrong?