The case of Town of Greece v. Galloway (docket 12-696) was one of five newly granted cases, all of which will be heard and decided in the Term starting next October. No current member of the Court was serving when the Court last ruled on government prayers in the case of Marsh v. Chambers, in 1983.
MORE: http://www.scotusblog.com/2013/05/court-to-rule-on-government-prayer/