Lunar and Planetary Institute






Planets and the Solar System
Activities for the Classroom

Build a Scale Model of the Solar System
Students can build a scale model of the Solar System, starting with selecting the size they would like their Sun to be.
One variant of this activity is to have the students model the positions of the planets themselves, wearing pictures or carrying signs of their designated planet. Another is to use fruits or other foods selected for their sizes to compare the sizes of the planets.

Modeling the Night Sky  
Students model the motions of some objects in the Solar System as they orbit the Sun, relative to background constellations.

Learning Planet Sizes
In this activity, learners use the concepts of greater than, less than, and equals to classify student height, object size, and planet size. They will build scale models of the planets based on their discoveries of planet size.

Earth, Moon, Mars Balloons
Students construct a scale model of the Earth-Moon system, both in terms of planetary sizes and distances. In addition, students make a scale model of Mars, and discover how far one might have to travel to visit the most Earth-like planet in our Solar System.

Building Blocks of Planets (Accretion)
In a demonstration, participants see an illustration of planetary accretion, modeling the formation of the Solar System.

Changes Inside Planets (Differentiation and Breakup)
Participants model the differentiation process where light and heavy materials are separated within a planetary body using gelatin. Then, participants model the break-up of a differentiated body using frozen hard-boiled eggs.

Differentiation Demonstration
In this 10 minute demonstration (similar to the one above), children observe a demonstration of planetary differentiation, the organization of planetary interiors into layers of different densities, to illustrate why Mars and other planets have cores, mantles, and outer crusts.

Recipe for a Planet
Recipe for a Planet is a 45 minute activity in which children build edible models of Earth and Mars to compare their sizes and illustrate their internal layers.