Biology has the great benefit of being maybe the most empirical science. Talking about animals, plants or the human body, are issues that kids of every age can understand and relate to. The situation changes, however, when we move to smaller scales such as cellular and molecular biology. There, keeping the right perspective becomes important, in order to maintain the connection of what is around and what is too small to see.
A very literal approach to that (and in my opinion a nice and simple idea for an introductory course) is the famous “Power of Ten” video where Charles and Ray Eames depict the relative scale of the Universe according to an order of magnitude based on a factor of ten, first expanding out from the Earth until the entire universe is surveyed, then reducing inward until a single atom and its quarks are observed.
The idea was introduced already in late 50s, when Kees Boeke wrote his essay “Cosmic View“, soon to be followed by the creation of the video mentioned above.
More videos following the same approach were later produced, such the “Cosmic Voyage” series, narrated by Morgan Freeman, but none kept the simplicity, and, therefore, straightforwardness of the original film. That is, until the recent explosion of app creation.
We now have excellent sources for the topic, that can be tried by students on any iOS/android device. Cosmic Eye (only for iOS) stays loyal to Boeke’s intuitive representation and is worth having a look. Demos can be found on youtube as well, for a demonstration to the class:
Another fun source, more like a game, is the Powers of Minus Ten, an advanced application where students can visit different levels of organisation in the body and have access to quizzes such as finding the right order of cell cycle events. The design team behind it seems very enthusiastic and they provide more goodies such as Lesson Plan Drafts based on the application.