"Ahu" are stone platforms on which many moai sit. There are 313 known ahu and 125 of these carry moai. The biggest, Ahu Tongariki is 220 m (720 ft), and had the most (15) and tallest moai.
And I remember as a second or third grader having some autonomy to go to the store if I felt like it, walk home, take my time, kick the can. We were on our own schedule after school, so that was cool.