I never seem to get more than half of True/False questions right. Either I circle the wrong thing, or my intuition is tricked by the wording. Since they are not usually worth too many points I neglect to go through a proof of my answer, and consequently I choose the wrong one. The problem is intensely magnified when the consequences of missing a question is the loss of twice (or five times) the value of the entire problem (say, losing 10 points, as opposed to getting nothing, on a 2 point problem).