Some areas of the country do throw the weight in youth competitions. If you or one of your athletes is scheduled to throw in a youth meet, you will need to contact the meet director and check what size weight they will be using for the age group.
In the sense of performing as designed, most radar detectors do detect the presence of police radar in the immediate vicinity of a speeding vehicle. Whether or not that information will actually prevent a driver from receiving a speeding ticket remains to be seen, however.
The word radar is an acronym derived from the words RAdio Detection And Ranging. It refers to the technique of using radio waves to detect the presence of objects in the atmosphere. Radar was designed shortly before World War II. Its primary purpose was to detect the presence of aircraft. Today, radar is used for a wide array of applications, but primarily to detect precipitation and other meteorological events.