Academic quarter (class timing)

An academic quarter (German: Akademisches Viertel, Swedish: akademisk kvart (ak or aq)) is the quarter-hour (15 minute) discrepancy between the defined start time for a lecture or lesson ("per schema") and the actual starting time, at some universities in Austria, Switzerland, Estonia, Finland, Romania, Belgium, Croatia, Slovenia, Germany, The Netherlands, Denmark, Norway, Portugal, Poland, Sweden, Serbia, Italy, Israel, Hungary, Greece, and the UK.

The quarter system dates back to the days when the ringing of the church bell was the general method of time keeping. When the bell rang on the hour, students had 15 minutes to get to the lecture. Thus a lecture with a defined start time of 10:00 would start at 10:15.

Academic quarter exists to a varying extent in many universities, especially where the campus is spread out over a larger area, necessitating the need for fifteen minutes for the students to walk from one building to another between classes.

In the German university system, lectures scheduled at a certain hour, with or without the addition "c.t." (cum tempore, Latin for "with time"), usually start 15 minutes after the full hour. If this is not the case, usually "s.t." (sine tempore, Latin for "without time") is added to indicate that the lecture will begin at the exact time.

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