The activity guides students to use sticks and rope to make a circle in the dirt and to use this to estimate the value of π. As long as students make a half decent circle they should be able to establish that π is between 3⅛ and 3¼  and closer to 3⅛. The activity ends with a discussion of how you can exclusively use rope to approximate π to any degree of accuracy assuming you can make percission measurements. 

The activity introduces students to how ancient Egyptians write their numbers. Students perform borrowing and carrying using Egyptian numerals. It ends with a discussion of Egyptian multiplication and division. While this activity is note directly related to π, I wanted students to be aware of how Egyptians perform arithmetic. This way they can imagine what it would be like to perform the necessary operations to approximate π on a following activity, though I will allow them to use modern base 10 notation and algorithms. 

The activity begins by introducing students to base 60 whole numbers and decimals, how to convert between base 10 and base 60, and how to add and subtract in base 60. Then the activity has students learn to write using Babylonian numerals and perform addition and subtraction using these numerals. The activity ends with multiplication and division which relies on using historical multiplication tables and reciprocal tables, which I have sourced translations from The Mathematics Egypt, Mesopotamia China, India, and Islam and Sherlock Holmes in Babylon respectively. Similar to the previous activity, this is not directly related to π. I will allow students to use modern base 60 notation and algorithms, but this way they can at least imagine what it would have been like. 

This activity takes students through examples of circles from Babylonian and Egyptian sources. These examples include explicit values of diameters, circumferences, and areas, which end up implying different approximations of π. The translations of these sources are sourced from A History of Pi, The Mathematics Egypt, Mesopotamia China, India, and Islam, and The Crest of the Peacock. It is important to remember that the ancients did not think of this in terms of π, but rather had rules for relating the different dimensions of a circle to one another. The activity ends with two different hypothetical explanations for the Egyptian rule relating the diameter and area of a circle taken from The Crest of the Peacock.

This activity is not strictly necessary to discuss the history of π, but is included in order to complete the picture of Egyptian arithmetic.  Egyptians exclusively used unit fractions and all other fractions were represented as simply as possible using a sum of unit fractions. This is achieved using an addition table from the Mathematical Leather Roll translated in  The Mathematics Egypt, Mesopotamia China, India, and Islam. Multiplication and division using fractions requires a table of doubles of unit fractions from the Rhind Mathematical Papyrus translated in the same source. 

This activity is not necessary to discuss the history of π. It is included in order to expose students to base 20 and the historical significance of having zero as a place holder. The activity begins by introducing students to modern base 20 and how to convert back and forth. Then there is a digression on Mixed Radix numbers systems including the Mayan system. It ends by introducing Mayan numerals and performing operations in this system. 

This activity introduces students to ancient and modern Chinese numerals. It also shows how Chinese mathematicians used counting rods to perform arithmetic. This is not directly related to π, but allow students to imagine how ancient Chinese mathematicians would have performed computations related to circles, which we explore in the next activity. 

This activity takes students through examples involving circles in ancient Indian and Chinese sources. These sources give our first examples of circling a square and an approximation of the √2. Similar to the Egyptian and Babylonian Circles activity it also includes rules for relating the dimensions of a circle to one-another. The translations of these sources are taken from The Mathematics Egypt, Mesopotamia China, India, and Islam and The Crest of the Peacock. 

This activity takes students through Hippocrates' squaring of the lune, which was an attempt to square the circle. It also takes students through the "construction" of Hippias' Quadratrix and a discussion of how its successful construction would allow us to square the circle. This is the first activity to require compass and straightedge. 

This activity takes students through examples from Egyptian, Babylonian, Chinese, and Greek sources that illustrate that the ancients had knowledge of the Pythagorean theorem. Then a proof of the Pythagorean theorem is presented from a Chinese source. The translations of these sources are taken from The Mathematics Egypt, Mesopotamia China, India, and Islam and The Crest of the Peacock. While not directly related to the history of π, the Pythagorean theorem is used repeatedly in Greek sources we discuss. 

This activity takes students through tabulation of early trigonometric functions in Greek and Indian sources. First students go through Ptolemy's derivation of the angle difference formula for the cord function. Then students go through Brahmagupta's interpolation formula to approximate values of the ancient Indian trigonometric function ardha-jya. The translations of these sources are taken from Pi: A Sourcebook and The Crest of the Peacock.

This activity takes students through Eratosthenes' measurement of the Earth's circumference. This activity is not directly related to the history of π. This activity is written specifically for Hanover, but can be adapted with some work using NOAA's Solar Calculator. 

This activity takes students through Archimedes' and Liu Hui's approximation of π using regular inscribed and circumscribed polygons. This is the first activity in which the historical figures are explicitly dealing with π. The translation of the original sources comes from Pi: A Sourcebook.

This activity is unrelated to π but is intended to give students a sense of some of the contributions of Islamic mathematicians. It takes students through Al-Khwarizmi's solution of quadratic equations and some of Omar Khayyam's solutions of cubic equations. The translations of these sources are taken from The Crest of the Peacock.

This activity takes students through two very different infinite representations of π. First it explains how Madhava used an infinite series representation of arctangent to approximate π. Then it takes student's through Viete's derivation of an infinitly nested radical formula for π. The translations of both these sources is taken from  Pi: A Sourcebook.

This very simple activity simply invites students to use pencil and paper to compute π by hand. 

This activity invites students to use Excel to compute the Snellius-Huygen bounds on π . These bounds are given as algebraic expressions of the area and perimeter of inscribed and circumscribed regular polygons. The translations of both these sources is taken from  Pi: A Sourcebook.

This activity takes student through Wallis' original derivation of a miraculous infinite product formula for π. This is the first activity that uses Calculus in an essential way. This source is taken from  Pi: A Sourcebook.

This activity introduces students to the arithmetic triangle, its properties, and the binomial theorem. It then introduces students to Newton's expanded binomial theorem, and takes students through Newton's derivation of π using his infinite series. This source is taken from  Pi: A Sourcebook.

This activity takes students through Euler's infinite product formula for sine and cosine, and how to algebraically derive infinite series formulas for different powers of π. The activity concludes with Euler's technique of finding continued fractions, and using this to derive a continued fraction formula for π. This source is taken from  Pi: A Sourcebook.

This activity shows students how to use a continued fraction formula for π to show it cannot be rational, and concludes with a rough idea of why π cannot be constructed using simply compass and straightedge. 

This activity takes students through the Indiana Pi Bill and other writings Edward J. Goodwin on geometry.