| − | [[Full Text of the United States Constitution|Article I, section 3]] of the [[United_States_Constitution|Constitution]] requires the [[United States Senate|Senate]] to be divided into three '''classes''' for purposes of elections. Senators are elected to six-year terms, and every two years the members of one class-approximately one-third of the Senators-face election or reelection. Terms for Senators in Class I expire in 2013, Class II in 2009, and Class III in 2011.<ref>[http://www.senate.gov/reference/glossary_term/class.htm US Senate Reference]</ref> | + | The dictionary definition of '''classes''' can mean many terms. It can mean a set, collection, group, or configuration containing members regarded as having certain attributes or traits in common; a kind or category. A "social class" are individuals who are grouped together based on [[economic]] or [[political]] proportions. That would be referred to as a caste system. Classes are also frequently used in [[education]] which would be a group of students who are taught together because they have roughly the same level of academic development. |