The best way for most kids to learn something is to let them experience it, and the universe is about to deliver a wonderful teaching tool right to our very doorstep! A comet named Pan-STARRS is reaching the inner solar system as we speak, and it's proving to be quite a good show in the Southern Hemisphere already. It should be visible in the Northern Hemisphere very soon - bright enough to see with the naked eye! This is a wonderful opportunity for kids to explore the mystery of comets, and have the expierence the appearance of one as it happens. Comet watching will be something to do with your kids every night at dusk for the next month or so.
This is the first appearance of this comet, making it hard to say exactly how it will behave, but predictions are being made that this comet with put on a good show for some time. It will be visible on low in the Western sky at twilight starting around March 5-7. You may need binoculars to see it at first and it will be low on the horizon. As March progresses it should be easier to spot in the night sky and will be visible longer. The best days for viewing will be March 12 & 13, because the only competing source of light after dusk on those nights will be the crescent moon. There's a possibility that this comet will be visible in the night sky into May!
NASA: How to Spot Comet Pan-STARRS
Comet visibility is hard to predict because of the nature of comets themselves. They originate in a 'cloud' of material that floats outside the solar system called the Oort cloud. There are trillions of potential comets in the cloud, mostly just frozen chunks of icy rock and gas. All it takes is for one to get a little nudge in the right direction for it to be it's way to the inner solar system - pulled by the sun. Comets are not uniform - variations in size, composition, mass and orbit are all factors in how a comet behaves, and how it looks from Earth.
Take advantage of this opportunity, and engage your child in observing this comet nightly if it's visible. Watching the comet first-hand will cement what they learn from the inevitable questions they'll be asking, and the answers they find may come from their very own observations! It really couldn't be easier, just go outside at dusk if the weather is clear and look West.