Unaccompanied minors should get special care, but they are sometimes being sent to accommodations for grown-ups, if they are 16+ years old.
Minors whose age is contested by the police or the asylum authorities and who cannot proof their age with reliable documents can be subject to an age assessment by doctors or medical experts as unaccompanied minors may get different treatment when it comes to deportation, living or other support than asylum seekers of full age.
The age assessment is based on an expert opinion and contains a combination of three different methods: Interview, inspection by a doctor (genital hair and genitals, beard, size, etc. basically a check of the whole body) as well as x-ray examinations of teeth, collarbone, and the wrist joint (carpus). In order to establish the age of the person in question an average value is being calculated. These examinations are scientifically disputed as the results are very imprecise. It can take up to 5 months before you receive the results of these examinations.