The Blocked Account for Minors was specifically created for students who want to come to Germany for their studies but are not yet 18 years old. In this case, the Blocked Account is opened by a parent in their own name, stating the child as the visa applicant.
All processes must be finished by the parent, just as with the regular blocked account. Fintiba issues all the relevant documents in the child's name and the payouts are set up to a current account that has been opened in the child's name.
More information on the entire process can be found here.