We all remember learning about "pi" in math class, right?

Your teacher probably made a joke that it's a math sequence, not pie.

But on Thursday, it was truly all about pie at Pies 'n' Thighs in Williamsburg.

March 14 is Pi Day as the date reads 3.14, the first three digits of the symbol pi.

The all day pie shop honored pi with $3.14 slices of pie.

The offering included all of their flavors, including banana cream , pecan bourbon and key lime pie.

"Nothing is ever that cheap, even if you go to a dollar store, things are more expensive so...I'm really excited about it," said Brooklyn resident Lexi.