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 This AAPT Digi Kit integrates geometric optics with biology as students explore light refraction through "lenses" made of clear gelatin and use hydrating polymers called "Water Pearls" to explore optics properties such as image inversion and focal length. The Gelatin Lens activity allows learners to model the function of the human eye, which is able to change the shape of the crystalline lens to adjust vision for near and far objects. This marvel of vision, known as "accommodation" can be imitated by squeezing the concave-shaped gelatin lens and drawing ray diagrams of the refracted light through different configurations. The "Water Pearls" activity can be used to model the way light refracts through a human or mammalian lens, then produces an inverted image on the retina (a process that is counter-intuitive and often confounding).