The potency of THC, the mind-altering chemical in marijuana, has more than doubled in the last twenty years creating a greater risk for impairment and a far higher risk of addiction. Video presents viewers with up-to-date information on THC potency and looks at how THC affects the brain, how you become addicted, how marijuana impacts brain chemistry, cognitive function as well as mental and physical health. Research experts and former teen users drive home this message: Marijuana is NOT a benign or safe drug. Stronger doses of marijuana can cause intense and disturbing reactions such as paranoia and hallucinations with permanent damage to cognitive abilities; marijuana limits your ability to learn and retain information; the stronger doses of THC cause more intense highs, putting teens at an even greater risk for car wrecks and other accidents; and marijuana use harms your brain, lungs, liver, heart, and reproductive health. Teachers guide included.