This article describes an easily made physical lung model for teaching about lung ventilation. It has rectified some major shortcomings of the bell-jar balloon model by having a fluid-filled “pleural cavity,” a dome-shaped “diaphragm,” and an inflated “lung” at rest. The model can be used to tackle some misconceptions about ventilation as well as to learn some difficult concepts such as the negative pleural pressure and pneumothorax.

A physical eye model made of a water balloon and a convex lens is described. It can be used to model how an image is formed in the eye as well as shortsightedness and farsightedness. The model is unique in featuring a fluid-filled “eyeball” with “intraocular pressure,” making it a useful tool for teaching about accommodation and glaucoma. Instructional ideas for the model are suggested.

The study adapts Anfinsen's Nobel-winning experiment of protein folding into biology investigation for secondary and college students. This experiment is significant for secondary and college science learning not only for its associations with some core concepts in biology, but also for its rich nature of science and science practices. The lab procedure of the original experiment was modified to be accessible to secondary biology teachers and students. A detailed lab manual and task sheet are available.