1 page. Includes bibliographic references. Studies show that marijuana interferes with attention, motivation, memory, and learning. Students who use marijuana regularly tend to get lower grades and are more likely to drop out of high school than those who don't use. Those who use it regularly may be functioning at a reduced intellectual level most or all of the time. This fact sheet briefly explores marijuana use by teens, marijuana may hurt the developing teen brain, and consequences of heavy marijuana use by teens (educational outcomes, life outcomes, reduced intelligence, reduced IQ). Also: perception of harm, and first time use.