In grade 9 today we celebrated pi day by looking at circles, measuring diameter and circumference and making a scatter plot.

We made a line of best fit using desmos.

Next we looked at the surface area of spheres.

We traced oranges to make circles with the same radius as the sphere.  We peeled the orange and filled the circles with the peel.

We filled 4 circles.  Each circle has an area of pi(r)^2, so this explains why the formula for the area of a sphere is 4(pi)(r)^2.

Grade 10s looked at the equation of a circle, and how a circle is defined by the equation x^2+y^2=r^2.

Grade 12s did the tootsie pop experiment.  The initial circumference is measured.

After sucking on the lollypop for a minute, the circumference was measured again

We kept a table of data

And now we are going to make graphs comparing circumference to time, surface area to time, and volume to time.

Happy March Break every one!  Have a happy Pi Day on March 14. (3/14)

Here’s the recipe I used for the butter tarts we ate today.

1 1/2 cups packed brown sugar
2 eggs
1/2 cup butter
2 cups raisins
2 tablespoons heavy cream
30 (2 inch) unbaked tart shells

Preheat oven to 325 degrees F (170 degrees C).

Cream the butter, sugar and eggs well. Add remaining ingredients and mix thoroughly.

Pour batter into tart shells, no more than half full. Bake for 20 – 25 minutes. Watch carefully!!–they’ll burn quickly.