Middle-aged kicks

He had not been a rebellious teenager - no campaigning posters and loud music for him. He had studied, done well, got on. But, now, everything angered him - from social injustice to supermarket queues. When he grew tired of ineffectual railing, he joined a campaigning movement and a political party. And, as he became aware of the irreplaceable value of his passing time, he gave up more and more of it to work with two local charities.
His walls and windows filled with hectoring posters. He joined a middle-aged, politically-aware rock band. He was late, but he was finally getting his teenage kicks.