Why advice about revising might need to be revised.
Revision charts, highlighter pens and sticky notes around the room are some of the methods people use to ensure information stays in their mind.
But now psychologists in the US warn many favourite revision techniques will not lead to exam success.
Universities, schools and colleges offer students a variety of ways to help them remember the content of their courses and get good grades.
These include re-reading notes, summarising them and highlighting the important points.
Others involve testing knowledge and using mnemonics - ways of helping recall facts and lists, or creating visual representations of the knowledge.
But teachers do not know enough about how memory works and therefore which techniques are most effective, according to Prof John Dunlovsky, of Kent State University.
He and his colleagues reviewed 1,000 scientific studies looking at 10 of the most popular revision strategies.
They found that eight out of 10 did not work, or even hindered learning.