There was limited evidence to indicate that extended school years produced negative impacts upon student behaviours among 13 to 14 year olds, but did not affect the behaviour of 9 to 10 year olds.
Roedd rhywfaint o dystiolaeth bod blynyddoedd ysgol estynedig yn effeithio’n negyddol ar ymddygiad myfyrwyr 13 i 14 oed, ond nad oeddent yn effeithio ar ymddygiad plant 9 i 10 oed.