Alberto
A stupid person who does not study, fails every test, and is so incompetent that his mother has to help him with basic schoolwork. It is used as a derogatory slur to call someone mentally slow or a retard, specifically someone who hangs out with kids from the Montessori school (referring to alternative schools which are sometimes mocked in Spanish schoolyard contexts as being for those with learning disabilities).
Alberto...
Automatically translated from Spanish
España