its illegal for someone over SIXTEEN to have sex with someone under sixteen... but once your over 16 your technically allowed 2 go out with who you want. tho i dont think a 24 year old and 16 year old would be very well recieved by people.
That's not true as a school girl in Aberdeen (aged 16) started dating her 44 year old teacher and he is only facing charges of breach of trust and contract.
It is not illegal for anyone over the age of 16 to sleep together what ever their age in most circumstances.
However there are rules regarding those whom work with children, especially teachers which prevents them from having a relationship with children even if they are 16 and work with them.