Children and adults alike share awe and wonder about the heavens. Combine this with ever-expanding technology and knowledge about astronomy, and you have the ingredients for a limitless variety of solar system projects for students of all ages. Understanding the relationships between everyday celestial objects, time and the geometry of the solar system is a worthy endeavor for students at all grade levels. These fun, brief projects, which combine online research with observations of the sky, require little in the way of equipment and are entertaining and illuminating for educators as well as children.

Many grade-school children understand that our moon is a spherical object that revolves around the Earth, just as Earth revolves around the sun. They also may be aware that other large heavenly bodies called planets revolve around the sun. This information can be used to introduce them to the idea that the planets themselves have moons. Some or all of the four largest of the many moons of Jupiter, the solar system's biggest planet, are visible on a clear night with a decent pair of binoculars. Students can be encouraged to learn their names, why we can see them from Earth at all, and how they relate in terms of size to the solar system's other prominent moons and its smaller planets.

Bonus: Why might bigger planets have more moons than smaller planets?

"A bright full moon was just peeking over the horizon as the clock struck midnight," reads a scary story, but that's incorrect. You can figure out the time of day the moon will rise and set based on where it is in its 28-day phase – new, waxing, full and waning – or, better yet, on what direction you're looking in if the moon is in a given phase and you know the time of day. Start by understanding why a full moon has to rise at sunset and a new moon appears at sunrise based on the geography of the solar system.

Bonus: There are 24 hours in an Earth day and 28 days in the lunar (moon) cycle. How much do moonrise and moonset differ from one day to the next? Are progressive moonrises and moonsets later or earlier with the march of the calendar?

Most Northern Hemisphere students probably know that summer days offer more sunshine and winter days less. They have probably also learned that the sun's rays are less direct in the winter than they are in the summer. Invite them to learn why this is the case by having them research the relationship between their own latitude, the time of year – hint: focus on solstices and equinoxes – and the 23.5-degree tilt of the Earth on its axis. Explain why, at noon on both the first day of spring and the first day of fall, the sun reaches a height of 55 degrees above the horizon at 35 degrees North latitude.

Bonus: How far north must one go before reaching a point at which the sun does not appear above the horizon at all for a period in the winter and also doesn't set for a period in the summer? Does this "line" have a name?