This year's season of plays gets off to a disappointing start. There will be 14 works showing in the National's three theatres over six days and written by mostly well-known playwrights for performance by schools and youth groups. Since the two writers who open the season have created major work in the past, the poor quality here is doubly disappointing.

The core idea of Mark Ravenhill's Scenes from Family Life looks as if it might have potential. Jack and Lisa are about to become parents but Lisa keeps vanishing. Stacy is also about to give birth but it is her Barry who vanishes. Soon the entire population of the world has gone, save for Stacy, her baby and Jack; and soon it is only Jack. Then everyone comes back again.

The performances that the director Keith Burke draws from 20 members of the Kildare Youth Theatre are pretty good, and Ross MacMahon shows real quality as Jack, making his initial amazement comical but true, and progressing through obsessive fatherly love to the howl of pain as a bereft survivor. But is the play a male fantasy of having a baby without a woman around? Or showing the human need for companions? Both seem possible but the play is not sturdy enough to give body to either.

Moira Buffini's A Vampire Story lacks even the sturdiness of a clear plot. Two vampires, mother and daughter, arrive at a small town; for 200 years they have preyed on human victims, and this time it will be schoolchildren and their teachers. Flashbacks to a Regency brothel unhelpfully complicate the story. Best lines are given to a sad, home-educated boy - “I used to have an imaginary friend but he moved out”. Other than providing roles for 19 actors from Hertfordshire County Youth Theatre the play is without point, and the actors, mostly under 16, are too inexperienced to counter the play's poverty.

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