Once a quarter I assigned a science demonstration for each student to present to the class. There are three levels to the assignment: Basic, Average, Challenge. Students practiced the Scientific Method and research skills them either gave an oral report, performed an experiment, or acted as a lead scientist and taught the class.
This is the paper I gave the students a week before their demonstrations. I also asked the students to identify orally their project choice, purpose, materials needed, hypothesis, and its application before he/she proceeded with the experiment.