hi welcome to silkysteps.
i linked this with k3d217 in unit 303 and split it into the different age groups adding in the implications for each section. for health and safety i included falls, suffocation, choking,burns, drowning, cuts and bruises,transport/car accidents, poisoning and how these would be different at different stages of development. implications for security you could talk about children needing less security and less supervision as they get older, safety gates, child locks on cupboards, coded locks on school doors in primary but not in secondary
hope this helps