The formulas used assumed no friction. Any difference between data sets on each graph would most likely indicate the presence of friction in the system.
 

Acceleration in the X-Direction without foil

Notice how the yellow, or predicted points, on the above graph are all shifted away from a=0. This suggests a resisting force was slowing down the motion in the x-direction of the stick.

Acceleration in the X-Direction with foil

On the above graph, the data sets seem to be the same, and no shifting is present.

Acceleration in the Y-Direction without foil

The first contact of the above trial seems off by a sign error. The same formula was used for the second contact and the contacts in the graph below. Because this is the y-direction, no shifting was expected because the force applied was primarily in the y-direction.

Acceleration in the Y-Direction with foil

Above the two instances of contact varied in relationship to the center of mass. In the first, the stick was hit significantly closer to the center of the stick. In the second, where a greater acceleration is noticed, the point of contact was closer to the end. The y acceleration values of the first instance of contact, at about 3/4 of the stick, are very close to those in the trial without foil hit at about 3/4 as well. This can be seen by comparing the y-axis scales.