One of the less well-publicised clauses of the new Company Law Reform Bill, currently before Parliament, is that the minimum age for appointment as a company director in England is to be lowered to 16. However, the Secretary of State will be empowered to allow those under 16 to be a director in different parts of the UK, should it be deemed necessary.
A recent Isle of Man case confirmed that a minor could be validly appointed to a directorship of a company there.
If your entrepreneurial children need the benefit of a limited liability company, or you would like to involve a minor child as a director of your company, then this will soon be possible. At present, however, any shares in the company which are allocated to them will have to be held in trust for them until they reach majority.