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.
A potentially useful and technically feasible area of development is radio frequency (RF) sensors to detect and monitor human activities associated with bomb making and bomb delivery from a standoff distance. RF sensors provide unsurpassed range, 24-7 operation and good penetration through building walls. Human body and limb movements also result in unique microDoppler features that can be detected easily. There are a number of ongoing through-wall radar sensing programs funded by the US government.