bunk off
先程と同じニュースから表現を拾います。
bunkと聞くと「(主に米・くだけて)(共同の寝室で)寝る(together)(仮の寝床で)寝転がる(down)」(『Wisdom英和辞典(第3版)』三省堂)を想起しますが、記事では、イギリス英語で「<学校など>をサボる(off)」(『Wisdom英和辞典(第3版)』三省堂)となります。(Shou-VR*)
School allows kids fag breaks to stop them bunking off school
Head of school allows children as young as 14 to take a 10 minute cig break
A school head lets her pupils have cigarette breaks because she says it stops them from bunking off.
http://www.mirror.co.uk/news/weird-news/school-allows-kids-fag-breaks-3215587