Half-back Matty Smith, who turned to rugby league despite being a promising footballer with Everton, has been given a two-year contract by St Helens.
Smith, who has completed a bricklayers' apprenticeship, represented England Under-18s in their recent Test match against France.
Saints have also signed two other youngsters from their junior set-up.
Winger Dean McGilvray has been given a two-year deal and prop Danny Cooper has signed a 12-month contract.