Here are my observations on common mistakes on the Water Lab:

Writing errors:

If it is a sentance, it needs proper capitalization, spelling, punctuation and sentance structure.
If it says "Explain", you need to elaborate on the underlying cause, outcome, physical reason. (NO: Does the Basilisk really walk? "No, it runs") No explaination at all is even worse.
Answer what is asked. If it is asking about shape, don't tell me size.
Don't tell me more than the answer to what is asked. It makes it harder to find the point and it will cost you points on the AP test.
If your penmanship is not legible, you didn't answer the question.
Write in pencil. Especially the data. If you make a mistake, erase. Don't scribble out or write on top.
Record data carefully. If your data does not match your explainations, I will start marking correct answers wrong because according to you, you didnt get the results you are describing. (Someone drew the meniscus upside down. That would only happen if the container repeled water.)
Slow down and let your hand keep up with your brain.
Reread your answers after you are finished and before turning the lab in. Take the same care you should give a test
Avoid using pronouns. "It bonds to it so that it isn't connected to it anymore and it sinks." Get the picture?

Not explaining the cause of the water staying in the capillary tube more than just "capillary action".
Not observing the Lizard video more carefully. Too many people wrote just what the narrarator mentioned (tail) when clearly it was not the only adaptation allowing it to escape that way.
Not explaining why humans can't walk on water except for our lack of tail.
Not understanding the role of weight distribution, not just pure weight on not breaking surface tension. Basilisk doesnt break surface tension, a cricket does.
Not listening (apparently) when I showed the class the microscope picture of the paper towel and explaining that the fibers created more surface area. So many people still said it had less or never mentioned area at all.
Not explaining the effect of the soap on the physical cause of surface tension. Most mentioned water attracted more to soap but not what that meant for surface tension.

Although almost nobody got this result (not that I saw or read) the plastic cylendar should have been NON-POLAR. and should have had no meniscus. Any thoughts?