It's 10 o'clock on a Saturday morning when the Kids university in Mainz opens its doors for "Crime time - how to write a detective story": the second in a series of 10 lectures aimed at youngsters aged between eight and 12.
"The response has been huge," says Professor Claudia Felser, the project's chief organiser, who is nearly trampled as more than 1,000 children rush into Mainz biggest lecture hall.
It was Tuebingen university in southern Germany which hit the headlines with the first Kids university two years ago, giving children the chance to ask "real professors" questions and let them experience the thrill of attending a lecture. Press coverage of the event prompted other universities to follow suit.
In Mainz Professor Felser is busy explaining some dos and don'ts about university lectures to the packed hall of children, such as listening to the professor or only asking questions at the end.
Soon "Crime Time", run by two professors of German literature, is in full swing. A murder scene is enacted and the children get to work as amateur detectives, pondering motives and asking questions; helping the "detective" to interrogate suspects. Professors point out all the elements necessary for a good detective story until the stage detective wraps up his case to thunderous applause.
The Kids university in Germany has become a phenomenon, with Mainz one of 80 campuses nationwide welcoming thousands of children each year for lectures, summer courses, workshops and practical seminars.
"The idea is to bring the academic world closer to the general public by opening up the campus for children and their parents," says Professor Felser. Presenting things in a fun way, she says, gets children interested in the worlds of literature, archaeology and science.