Pi Day celebrates the mathematical constant π (3.14). It is celebrated in countries that follow the month/day (m/dd) date format, because the digits in the date, March 14 or 3/14, are the first three digits of π (3.14). Pi Day was founded by Physicist Larry Shaw in 1988.  – From timeanddate.com

Happy Pi Day, everyone!  The "traditional" ways to observe Pi Day are to make terrible puns (if you can't think of any, ask the nearest mathematician...they'll be forever in your debt), and eat pizza.  Among bakers, of course, Pi Day is observed by making a pie.  

You could, of course, make Venison Pie, or Carrot and Nut Pie, or Steak and Parsnip Pie.  I got those titles from a little book called simple Pies, gifted to me by the Office Manager.  I open it every once in a while just to contemplate the horror of Tongue Pasties.  

Or, if you're not feeling quite that intense, you could make this Lemon Meringue Pie.  Ah yes.  Given a choice between Greek Lamb in a Blanket and Lemon Meringue Pie, guess what I choose?  

Notes

This recipe is for a gluten-free pie.  If you do not want a gluten-free pie, you can use regular graham crackers (or pre-made graham cracker crumbs) in place of the gluten-free graham crackers in the crust.  In this case, you may need more butter in the crust, perhaps as much as 4 tablespoons in total.  

I used Schar's Gluten-Free Honey Grahams for the crust.  The crust required exactly half of a 160 g package.  

As the title suggests, this recipe makes a pie that, although small, is toweringly-high with meringue.  If you prefer less meringue, you can use 2 egg whites instead of three, and reduce the sugar in the meringue to 3 1/2 tablespoons.

It turns out that not everyone likes meringue!  In my own survey of four people, not selected at random, two loved meringue, one didn't care for it, and one shrugged.  If you do not care for meringue, you are completely free to leave it off and just enjoy a nice lemon pie in peace.  I won't judge you.  Maybe a little whipped cream on top?

Inspiration

The graham cracker crust was adapted from The Fannie Farmer Baking Book.  I had to experiment a bit to get the right ratio of butter to crumbs.   I am not sure why; it may be that gluten-free crumbs do not absorb butter the way regular crumbs do.  

The pie filling itself is a hybrid: I used the ingredients from The Fannie Farmer Baking Book, but the method that accompanied them defeated me.  I won't bore you with the details; suffice it to say that my first attempt could have been used to caulk a schooner.  It did have a pretty good flavor, though, so I decided to try the same ingredients with a more traditional cooking approach, and that worked very well.