You dream of the big test and something terrible happens - you've forgotten your calculator, you can't find a pencil, or your mind is blank. It happens to everyone at some point in their lives. Dreams of tests and exams are very common because our lives are full of tests in many forms. When we are young and still in school, tests are still the greatest measure of your success.

Dreams of a test which occur leading up to an actual test in school refer to our anxieties about performance. You study and study but until the test is actually over, you won't know if it was a success or your studies had paid off. This kind of absolutist thought leads to great insecurity. It would be better to relax and reflect upon previous success and remember that a single test is not the same as an accumulation of success over a lifetime. Everyone makes mistakes at some point of time.
When there is not a true test coming up in your waking life but you are having test anxiety dreams, this may occur because you are associating stress in your daily life with the same feeling of stress that you had as a child in school. It is likely that you are feeling judged at work or at home. Perhaps this judgement is actually coming from within yourself.
Many test dreams focus on time. You might arrive too late to the exam, or suddenly run out of time, or are caught staring at the clock and time just flies by. This symbolizes our fear of time, and particularly an anxiety that we can never have enough time to prepare completely for life. Life is a process, and there are thousands of hours that could be put into studying various subjects or activities. We can never become experts in everything and we all have an inner fear that we will not accomplish everything we would like before we die. It is important to remember that we are all in the same boat, and that other people actually understand this as well.
Sometimes we have the highest ambitions for ourselves, and much higher expectations for ourselves than others. Most people who have test dreams are actually driven by a strong desire to succeed, and it is unlikely that you will not meet that success.