Several situations can combine to cause a block as you engage in academic writing. This block is what is usually referred to as writers' block. The number one culprit is anxiety. As a student the best thing to do is probably talk to your tutor. Let's look at a few case scenarios and see if we can find solutions for them.
a. Attempting to start your academic writing without any previous preparation.
A student will naturally get stuck doing this. It is counterproductive. To quickly get out of this situation, use invention strategies. Write down your primary ideas in bits and pieces; this will give you a clearer picture of what you want to write. Develop these bits and pieces and you have your outline. Having an outline makes it easy for you to plough along. Remember that a good academic writing does not materialise overnight.
b. You have a topic that you consider to be boring.
A boring topic can effectively kill the creative spirit in you. To get past this, find an aspect of the topic that is of interest to you. Tackle your essay from this stand point. You may be pleasantly surprised to find you actually enjoy the topic. Another alternative would be to talk to your tutor assuming you have one. Discuss with your tutor how you can personalise your topic and make it speak to you.