SIXTEEN-year-olds are worth £2.1 billion but almost half do not know the difference between a credit and a debit card, a survey showed today.

Three-quarters are ignorant of what a direct debit is, while 49 per cent would not feel confident filling out a cheque, according to the poll for the Royal Bank of Scotland Group.

Eight out of 10 teachers who responded to the survey said teenagers needed to learn more about how to manage money at school.

And parents need to step up how they explain money to children.

The survey showed that teachers believed that a third of Britain's secondary schools were not teaching personal finance to their pupils.

On average they scored less than five out of 10 in a multiple choice finance quiz, which tested their knowledge of banking, savings, pensions, mortgages and tax.

The survey showed that 57 per cent of 16-year-olds did not know how long it normally took to pay off a mortgage (25 years), while 66 per cent did not know an annual TV licence cost £116.

Benny Higgins, retail chief executive of The Royal Bank of Scotland Group, said: "Our research reveals a worrying knowledge gap among teenagers, and a critical need to teach them basic facts about finance.