[header] How to build an ant farm [title] Get two glass jars with lids. [step] You'll need a large jar and a smaller one that just fits inside. The dirt and ants will be placed in the space between the small jar and the large jar. 
The small jar functions as a way to take up space in the middle so that the ant colony will build tunnels and lay eggs close to the outer edge, putting these processes in plain view. Skipping this step will allow the ants to burrow deep toward the middle of the jar, which they'll naturally want to do.