Shouldn’t we make a bigger fuss over Jefferson’s birthday? And didn’t we just miss it?
Thomas Jefferson was born April 2, 1743. Had he not died on July 4, 1826 — the famous day that both Jefferson and John Adams died, the 50th anniversary of the Declaration of Independence — he’d have been 264 years old this week. The republic he helped found, and whose second revolution his presidency cemented, is 218 years old. That the republic survived for more than 20 years without major changes, or violent revolution, was perhaps a surprise to Jefferson, who famously wrote to Madison that one generation could not write a contract to bind a future generation, even in the form of a constitutional government.
That the republic has survived for 200 years past one generation might strike him as some sort of miracle, evidence of the “hand of providence” that Franklin guy and the Washington guy often mentioned.
But wait a minute: Was he born April 2, or was he born April 13?
England and the English-speaking world were slow to adopt the Gregorian calendar, promoted by Pope Gregory in a reform of calculations for the dates of moveable feasts in the Catholic Church. When Jefferson was born, Virginia was still on the Julian calendar. When England, and the U.S., belatedly adopted the Gregorian calendar a few years later, some dates were shifted by up to 11 days. Jefferson’s birth date was one of those, as also, famously, was George Washington’s. 
So, while his family’s Bible may have recorded April 2 as his birth date, in the new, Julian calendar, the date was April 13. We know this because the Wikipedia article notes the date as “N.S.,” or “New Style.”
A warm-up exercise for high school students could involve the translation of dates of birth for patriots, from the Julian to the Gregorian calendars. This issue is not directly treated in the Texas Essential Knowledge and Skills (TEKS), but certainly the method of measuring the year is a major part of the march of technology, and worth spending a few minutes’ consideration for high school students in U.S. history.
Whew! That gives us most of a week to plan appropriate celebrations . . .
Good source: The Thomas Jefferson Digital Archive at the University of Virginia
Millard Fillmore's Bathtub 