This 20-piece kit comes with a storage box and a 25-page activity guide. Students are introduced to the concepts of straight-line propagation, transparent, translucent, and opaque materials, reflection and refraction, images formed by lenses, colors, and the spectrum. Kit contents include three lenses, two screens, two plane mirrors, two prisms, five cellophane color filters, three lens/mirror supports, a plastic beaker, a flashlight with batteries, a candle, activities guide, and a storage box.