Sidewalk chalk

Sidewalk chalk is typically large colored (and sometimes white or cream) sticks of chalk (calcium sulfate rather than rock chalk, calcium carbonate) mostly used for drawing on pavement or concrete sidewalks. A single piece of chalk is called a schibel. It is sometimes used by children to draw a four square court or a hopscotch board. Blackboard chalk is typically shorter.

There are several different types of sidewalk chalk, typically coming in solid-colored sticks. 3-D sidewalk chalk sets, in which each stick of chalk is created with two particular colors that appear 3-dimensional when viewed through the 3-D glasses that come with the chalk, also exist.

Sidewalk chalk can be cheaply homemade.

Sidewalk chalk is used at some universities to advertise for events, especially where there is much concrete. Prohibitions are set for where students can chalk, usually limiting it to areas that will be washed away with rain, or areas which are set to be cleaned of chalk markings.

Some teachers promote use of sidewalk chalk on a carpet as an interactive teaching tool.

Although sidewalk chalk is created to allow people to draw on sidewalks or pavement, some law enforcement agencies may prohibit sidewalk drawing in certain areas without first being requested for authorization.

On September 16–17, 2006, a global event was held to promote peace through sidewalk chalk drawings. Chalk4Peace was a project planned by an artist from Arlington, Virginia named John Aaron, who asked children and teens from the age of eight to age eighteen to participate in groups across the world to draw chalk drawings that would illustrate peace for one of the Chalk4Peace events. Designated areas on sidewalks, pavement, and concrete were used for the participants to draw on while volunteers took pictures of the street paintings. Aaron used his own money and donations to provide sidewalk chalk to areas of the world that he believed did not have access to good quality chalk.

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