Cinnamon Pinwheels

I got this recipe from Family Studies (Home Economics) in high school. Sorry it's in metric.

500 mL flour
20 mL baking powder
2 mL salt
125 mL shortening
225 mL milk
100 mL brown sugar
30 mL cinnamon
butter

Sift together flour baking powder and salt.
Cut shortening in with two knives.
Add milk; stir with fork to make a soft dough.
Turn dough out onto lighly floured board; knead gently 8-10 times.
Roll into rectangular shape 1/2-1 cm in thickness.
Spread with butter and sprinkle brown sugar and cinnamon.
Roll up in "jelly-roll fashion" and slice into 1-2 cm slices.
Place pinwheels onto ungreased cookie sheet.
Bake at 220`C for 12-15 mins. (10-15 pinwheels.)