These links need considering in the light of (i.e. together with), the particular subject you are studying.
Academic Writing is specific and the link that follow may help you understand how to focus on the styles of writing required of you when writing for an Academic Purpose, particularly in Examinations
(Try the widget on the EAP Foundation page EAP English for Academic Purposes)
Here are the three useful links, One has google online pages on Essay Writing (it is a Google Books link to a commercial but useful book and it’s sample pages). One is a website dedicated to English for Academic Purposes and the other is a Uni link.
Try to remember to plan everything, a good tool to remember and focus on the question task is:-
Use 10 to 3
List ten relevant subject words
Find three ideas to develop.
Try using this process often.
Take care not to confuse seemingly similar or the same words (but different) used in different subjects e.g.
Elasticity in ‘Design and Textiles’ or Economics
Branding or Re-Branding in Business or Geography