How do we get more young people into the theatre? One answer is to put them on stage. This admirable season, now in its 10th year, does just that, by getting youth groups from around Britain (and currently Cyprus) to present new plays by seasoned writers. Even the on-stage award of a cactus to the chosen groups serves, I suppose, to remind them that theatre has its fair share of pricks.
Each night two shows are presented; the opening Cottesloe pair proved that theatre can be a good way of articulating teenage fears. First was Tamsin Oglesby's Olive, which offered a dark, Angela Carter-like fairy story about the terrors of adolescence. Reared by adoptive parents, the 16-year-old heroine was reclaimed, for cloudy reasons, by her natural father, a bullying zealot who chopped off her fingers.
Even in her maimed state, the heroine married a land-owning Prince Charming, only to be further persecuted by an evil mother-in-law who tried to kill both her and her newborn baby.
Oglesby's play isn't just a Grimm fantasy about adult cruelty. It also deals with a country divided by class, language and biblical argument. And it seemed no accident that it was presented by North Down Youth Drama from Northern Ireland. You felt these teenagers knew a thing or two about religious bigotry and fierce economic divisions. And Patricia Irvine's expressive production kept the action poised between fairy-tale myth - with a peripatetic Peter Brook-like chorus clutching bamboo poles - and emotional reality. Sarah Young endowed the victimised Olive with a touching resilience while Nikki McNarry was sexily sinister as the wicked mother-in-law who, hearing of her son's marriage, announced: "Your father would turn in his vault."
The idea of teenagers as victims of adult conspiracy also permeated The Exam, written by Drop the Dead Donkey's Andy Hamilton. As three kids wait to sit an exam, we see the dual pressures they are under from fiercely competitive parents and from their own expectations.
Intriguingly, Hamilton also suggests that high-fliers are just as haunted as the natural losers; and the teachers add to the nightmare by cocking up the system or parading their own sexual traumas.
Hamilton's play is short on action and could push its indictment of our exam culture further. But the performance by St Mary's Youth Theatre, Leeds, was prodigiously heartfelt.
Watching these characters suffering premature ulcers or being bombarded by parental cliche ("Just do your best"), I suddenly felt mightily glad I wasn't young any more.
· Until July 16. Box office: 020-7452 3000.
