The mysterious reaches of outer space can spark your middle-schooler's imagination with dreams of fantastic sci-fi adventures borrowed from his favorite books and movies. But astronomy is much more than exploring the far reaches of space in faster-than-light ships and encountering alien races, friend and foe. Practical applications of astronomy include learning about the sun's life-sustaining energy and influence on the weather, seasons, tides, eclipses and time-keeping. Astronomy activities for your middle-schooler can build on the basic knowledge taught in elementary school to expand his scientific observation skills and knowledge of the tools used by astronomers to discover and describe what's "out there."
With the exception of the North Star, the visible star field moves through the sky by season. Some constellations appear only at certain times of year depending on your location on the planet because of Earth's rotation and orbit. Your middle-schooler can use a planisphere or star wheel to orient herself to the appearance of the night sky in any given season or month. The planisphere acts as a direction finder to tell her which constellations are visible and in what part of the sky. You can buy a ready-made star wheel at many learning or science supply stores. If you cannot obtain the commercial variety, your middle-schooler can search online for printable planishpheres to cut out and assemble to assist her in making star observations. Challenge your middle-schooler to go beyond the simple observations of his younger years and keep a journal of a series of observations over several months, noting the relative position changes as the stars cycle through the sky.
Star Life Cycle
The sun is the closest star to Earth. It gives off light and warmth that sustains life on Earth by helping plants make chlorophyll and growing into healthy food sources for humans and animals. The tilt of the Earth toward and away from the sun in seasonal cycles causes changing seasons and weather patterns, and directs ocean currents to create tides. The life cycle of a star helps your middle-schooler better understand the stars' profound influence on nearby planets. Observing the colors in a campfire or candle flame can spark discussion about which colors are hottest and how stars are classified by their color. Read books or websites that describe the different stages of a star's life from a stellar nebula to an average or massive star, a red giant or supergiant, a planetary nebula or supernova to a white dwarf, neutron or black hole. Your teen can paint a poster illustrating the star's lifecyle or build a 3D model or mobile, including the significance of the various colors and interesting facts about each star type.
The Solar System
By the time your teen reaches middle school, she will probably have learned some catchy rhyme, song or mnemonic regarding the order of the planets in the solar system. However, you can extend this basic knowledge by having her identify and explore other stellar objects in the solar system, such as the asteroid belt, meteors and moons. Go beyond a basic poster diagram and challenge your teen to compare planetary sizes and calculate a relative size and distance scale for the distance between planets. Based on that scale, match each planet to a an object such as a whole walnut, a pea, a grain of salt, a golf ball, a tennis ball, a baseball, a soccer ball or a basketball and create a diagram of the solar system. Glue each representative object to a black length of poster paper long enough to allow for the appropriate relative distances between the planets.
Your teen most likely has heard somewhere in elementary school that he lives in the Milky Way galaxy. But an interest in astronomy activities is an excellent excuse to point out that galaxies come in many shapes and sizes. They are made up of thousands of stars and expand outward over time causing the stars to slowly drift apart. Your teen can observe what this might be like with a simple bread dough galaxy experiment. Using fresh or frozen bread dough or a can of refrigerator biscuits, press four to five raisins, nuts or dried cranberries into the dough top center, very close together, even touching. Bake according to recipe or package directions to let your teen observe how the topping pieces move apart as the heat swells and expands the dough. Another visual astronomy project is to create a 3D galaxy map in a box. Spray paint a large, open box top black for the backdrop. Using the picture of one type of galaxy as a guide, cut out stars in appropriate sizes using white or yellow poster board, tin foil or glow-in-the-dark paints. Hang the stars from the ceiling inside the box at varying depths, using different length yarn or string hangers to make your stars form your chosen galaxy pattern.