Fit the convex lens onto the telescope, and it’s just like the one invented by German astronomer Johannes Kepler! Fit the convex and concave lenses onto the telescope, and it’s just like the one invented by Italian scientist Galileo Galilei! Assembling the lenses will teach you about how light travels. Experiment with making a telescope and a microscope using convex and concave lenses. Science guide included (68 color pages).