Note: In the formula below, the highlighted variables labeled as column A, column F, etc., in Excel as in most spreadsheets are replaced by the actual cell name. Take for example, a cell in column G and row 7.  If the cell is in column G and in row  7 the cell is named G7.
So, the formula in Column J  below which is written =(360/Column H)*Column I, in Excel  actually is  written with the cell names.  The formula is written in cell J3 as: =(360/H3)*I3. A nice thing about spreadsheets is the fill option for formulae. To make the formula work in all the successive rows of Column J, we click on cell J3 to activate the cell, then without clicking, lay our mouse on the small square at the lower right-hand corner of the rectangle surrounding the active cell until the curser turns into a thin plus sign, click and hold down the left mouse button, and while holding the left mouse button down, drag down to fill our formula in the cells below. This is called a fill down.

Column A: Site Name — School Name

Column B: City

Column C: State

Column D: Country

Column E: Latitude - of reporting site.

Column F: Longitude -of reporting site.

Column G: Length of shadow of a meter stick at local noon time. (we will leave this one out next year — kc)

Column H: The angle of the Sun at noon.

Column I: The Equatorial Distance-To understand what we are doing here, just think about why we take our readings at our local noon time. Imagine that we are lining up all of our schools at the same place on the globe, longitudinally, say at the Prime Meridian. The only distance between the schools would be the north-south distance. Instead of comparing the distances between the different schools as we have in the past, this year we are calculating using the equitorial distance, that is, the distance between each school and the Equator.
Now to find the circumference, we use Bali Online's site called HowFar is It, where we enter the latitude and longitude of the school and the the latitude and longitude corresponding point on the Equator directly north or south of the city.

Column J: Circumference Estimate-Now that we know the arc of the Earth formed by the distance from the school to the Equator, Column I, and the central angle of that arc which is the same as the Sun Angle, Column H, at Noon on the Equinox, we make our formula to find the circumference of the Earth.. (In this project the first site is the location of the school. The second site is the Equator. The distance is the perpendicular distance from the location of the school to the Equator. Since we chose our second site to be the point on the Equator closest to our first site and the time to be at Noon on the Vernal Equinox, the sun angle at our second site is 0°. Therefore, we do not need to do the subtraction that Eratosthenes did because we would be subtracting 0° from our sun angle. — kc)

You might remember that the size of an arc of a circle is the measurement of its central angle. Also, we chose the second site to be the point on the Equator closest to our initial site at the Vernal Equinox so that in this table, the central angle is the same as the sun angle. We posted a lesson to demonstrate this concept. Now to find the circumference estimate, multiply that one degree length by 360.

The Excel formula which we use is:
=(360/Column H)*Column I

Column K: The deviation from the Actual Circumference-To find this number we subtract the actual circumference from our estimate in column J, divide the answer by the actual circumference, 40008 km. Since we only want the distance and not the signed direction, we find the absolute value of it. Therefore, it won't be negative.

The Excel formula which we use is:
=ABS(40008-Column J)