Countries which have their employment age set below the school leaving age (mostly developing countries) risk giving children the opportunity to leave their education early to earn money for themselves or their families.
Children aged 13 and 14 may be employed in non-industrial establishments, subject to the condition that they attend full-time schooling if they have not yet completed Form III of secondary education and to other conditions which aim at protecting their safety, health and welfare.
This provision (as stipulated) applies solely to England and there is no legal requirement for an individual to be either working or remain enrolled in educational facility, above the age of 16, in any other UK nation.
From there they must be "learning or earning" which means they must be employed at least 25 hours a week, or be in full-time education or be in a combination of both part-time employment and part-time education which adds up to at least 25 hours a week until they turn 17 or complete Year 12 or equivalent, which ever comes first.
Victoria – 17; Western Australia – 15; NSW – 17 (if they want to not do their HSC they need to be working at least 25 hours per week or at TAFE studying until they turn 17); Tasmania – 17.