Flowers for Algernon is a great text for looking at psychology, character development, and progression of events. Note, you can use any version of the story – textbook adaptations, the short story, or the novel. I have kept this open enough to use any of the adaptations.
In this activity set, students will play the role of psychologists closely studying the case files of Charlie Gordon. They will track his progression through the experiment, make inferences, and ultimately create a report where they look at the "Algernon-Gordon Effect," make predictions about what occurs after the story, and otherwise back up their thoughts and opinions with "data" from the text.
This can be used as a portfolio writing piece / large graded assignment. This can be used as an informative, argumentative, or narrative writing piece, depending on how you spin it. There is also a possible discussion group activity to wrap this up after students create their reports.
This can be used with 8th graders or high schoolers, depending on the version of the story that you use. The novel, of course, contains more adult content.