Links to studying several different subjects including math, biology, chemistry and physics. Many have the same basic steps. New ones here is are using 2 different texts for studying (get a second one from a library, etc.) and to review the material from class immediately after class and then 8 hours later to increase retention.
One of a series of biology videos. This one starts by discussing carbon, covalent, ionic and Hydrogen bonds necessary for understanding much of biology. Not your traditional lecture.