I feel I have a pretty good understanding of position vs. time graph and velocity vs. time graphs. Those are both pretty straight forward and easy to follow.
Position is definitely the easiest to graph because you just plot the points and BOOM. You have a position vs. time graph.
I believe I'm strong in velocity vs. time graphs as well. Just finding the slope of a line to get the velocity comes relatively easy to me. I only say relatively because things with math are not my strong point, but I am improving.
I do, however, still struggle with acceleration vs. time graphs. I've definitely gotten better with then, but I still often get confused. I understand that the slope of a velocity vs. time graph is the numerical value of acceleration, but I have a hard time remembering when acceleration is positive or negative. I'm really having trouble understanding how an object can be speeding up, but have a negative acceleration, and vice versa.
Overall, I have a pretty good basic understanding of everything for the three graphs, but going deeper into acceleration vs. time confuses me.