Gravity is the force which acts on both pencils to bring them to a horizontal position. The center of gravity of the longer pencil is much higher above the table than that of the shorter. Therefore, in the longer pencil, more mass must fall through a longer distance with a longer arc. This takes more time.

Student is able to communicate what happens to the two pencils when they are released at the same time in relationship to the COG (center of gravity). Student is able to communicate something of what happens to the two pencils when they are released at the same time in relationship to the COG (center of gravity). Student is able to communicate that the short pencil falls much faster than the long pencil. Student is able to communicate that both pencils falls when they are released at the same time.