Exploratorium
Exploratorium: Science Snacks: Salty Pits
Investigate the effectiveness of different deodorants at combating armpit bacteria. Involves growing bacterial cultures on agar plates.
Success Link
Success Link: Microorganisms
Lesson plans to examine bactieria and how they grow. The main lesson page indicates that there are seven training labs, but there are only two operating links. Those two are worth exploring.
BiologyWise
Biology Wise: What Is Mannitol Salt Agar?
Mannitol salt agar is a medium used to grow bacterial cultures in a laboratory. Read here about its composition and how it works.