The foundation says it has sold about 20 million of them.

But the foundation says its approach can do just as well if not better, even with the poorest of students.

The Northeastern states are particularly in need, the foundation says.

The foundation says its programs currently touch about 8 percent of the nation's public high schools.

The foundation said it was no longer running those ads but did not say when they stopped.

With about $3 billion in assets, the foundation says it is the nation's 13th largest.

The foundation has said it plans to sell some or all of its more than 15 million shares.

The series has presented more than 1,500 acts to about 2.5 million people, the foundation said.

The foundation said there was "no truth to any of the allegations made in the story."

The foundation and the company said they had taken steps to avoid any conflicts of interest.