Paul, a 3rd grader, finds a pattern

I was working with Paul and a rotogram, to find   the sum of the angles of a polygon. Paul had difficulty with the idea of rotating clockwise and counterclockwise. Later when his Dad came in he told me that they have all digital clocks in their home, except for one.  So Paul was not sure how to read a regular clock.

We made a table of values where x = the number of sides of the polygon and y= the sum of the interior angles.

Paul noticed that  the 360° was one circle and 540° was 1 1/2 circles.

In looking for a pattern in the table he made 2 observations. "In the 100's, odd numbers are  getting higher". and "In the 10's even numbers are getting lower".