How can parents teach self-discipline and independence in adolescence?

In From Childhood to Adolescence, Montessori writes, in reference to the adolescent, “The feeling of independence must be bound to the power to be self-sufficient, not a vague form of liberty deducted from the help afforded by the gratuitous benevolence of others.” To support the young person’s developing sense of independence, families must provide opportunities for the adolescent to authentically contribute to the care of themselves, others, and the environment within the family and the surrounding community. The adolescent must take on this work without unnecessary adult interference, mirroring how the adult supported the development of functional independence with the young child (“Help me to do it by myself”) with only the necessary guidance. This requires courage and faith from the adult but supports the adolescent “in making him feel himself capable of succeeding in life by his own merits” (From Childhood to Adolescence). 

Group of adolescents cooking in a Montessori class