Topics: Neurotransmitters, central nervous system, synapse, the synaptic cleft, and drugs.
This assignment is best delivered after a lesson on the neurotransmission process. Students in a psychology or anatomy class should have learned about how neurons send messages to one another, and have a general knowledge of what happens in the synaptic cleft between two neurons.
Students are asked to research the effects of different neurotransmitters on the brain/body, and to find drugs that use or affect those particular neurotransmitters.
Additionally, students are tasked with creating a diagram of how two particular drugs affect the neurotransmission process. I often recommend using the University of Utah's "Mouse Party" website, although some might find the content to be too edgy.