Emily Ekins, writing for Cato Institute:

A new national survey from the Cato Institute, conducted in collaboration with Morning Consult of 2,253 Americans ahead of July 4th and America’s 250th anniversary, finds nearly half (46%) of Americans don’t know what America’s 250th anniversary commemorates. A little more than half (53%) correctly answered that it was the adoption of the Declaration of Independence.

I am not at all surprised by these results.