Headlines describe Martin Lewis as a 'modern-day Robin Hood,' or some sort of debt-solving saint. In short, he is fast becoming the man most of us turn to when we need financial advice, writes Andy Welch Martin Lewis is the self-styled Money-Saving Expert, a regular fixture of TV, radio and newspapers and the brains behind a hugely successful website.

With a degree in government and law from London's School of Economics and a post-graduate qualification in journalism, he ended up working for the BBC's business unit, before going on to more broadcasting and media work.

Martin is now the country's most-recognised consumer champion, famously highlighting the campaign to reclaim wrongfully taken bank charges.

It is little wonder producers of ITV's Tonight With Trevor McDonald asked him to deliver a Teen Cash Class to a group of 15-year-olds. The premise was simple - Martin would go to a school, spend a day with the children and give them basic advice on becoming more successful consumers.

The results were astounding. Taking home Martin's advice and helping their parents change their ways, the dozen-strong group managed to save a massive £5,050.

"The figures don't really shock me - I always say the average UK family could save between £2,500 and £5,000 per year following my tips - but I wasn't expecting to find that, as a nation, we're so financially illiterate," said Martin.

"I didn't think spending just one day with school children who know nothing about these issues would be enough to save their parents that much money."

His latest book, The Three Most Important Lessons You've Never Been Taught, is based on the advice he gave the school children, and aims to drive home three basic, yet totally crucial mantras in order to change the way we think as consumers.

The first lesson challenges how we feel about companies in general. As Martin explains, they are not our friends, no matter how nice they are to us.

"The first rule of being a consumer is that a company's job is to make money, and yours is to stop them," he explained. "Until you understand that, you're never going to be a good consumer. "

The second lesson in the book is about debt. It's a massive subject, but we have to think differently about it now. Many people say neither a lender nor a borrower be' but that is outdated. It is wrong and dangerous," he continues.

"Companies borrow money, governments borrow money, so there is nothing wrong with us borrowing money. The problem is we are a nation educated into debt when we go to university, but we're never educated about debt.

"If you want a house, you are going to have to get a mortgage. If you want higher education, you are more than likely going to have to borrow money, or if, say, you move to the country and you need to get to work, you are going to have to borrow money to buy a car.

"The problem in this country is nobody understands how to borrow. There are good ways to borrow money, for example a student loan or an interest-free overdraft, and bad ways like credit cards. No one differentiates between the types of lending; we just say don't do it'.

"I have a simple phrase that I use in the book that goes debt isn't bad, bad debt is bad'."

The final chapter in Martin's book urges us not to be blindly loyal to the companies that provide us with services, and that we should make businesses work for our custom.

"I asked the kids in the class who they thought got the better deal on car insurance - existing customers who've never had an accident, or new customers. "Strangely, they all said the existing customer, which is completely wrong. The existing customer is actually subsidising the new customer! "All readers of this article should do this: get your renewal quote from your insurance company, then enter exactly the same details with them as a new customer. You'll often find the new quote is 20-25% cheaper than your previous quote. That's the fine we pay for loyalty, and it's even more on mobile phones." Although we can all learn from Martin's latest book, the responsibility, he says, should really be down to the Government. "I don't think there's anything more important we could do in our society right now than teach consumer and financial education in schools," he says, definitely. "My argument is that you get everything else in school - sex education, cookery classes, everything - but isn't it outrageous that, considering the modern, massively competitive consumer economy we live in, we don't have financial education in schools? It's now been made voluntary? Why? Why isn't it compulsory? "One of the main problems is, teachers can't teach it. I spoke to the teachers in the same school I did the Cash Class in, and they were lovely people, but many of them were in a similar boat to the kids' parents. "We have fundamental mis-education that spreads right across our society. We don't have the ability to educate either, so I think we have a real, proper national crisis about to develop because of this. But it's not financial education we need most - what interest rates are and how cheques work - but my view is that we should really have consumer education in schools." If schoools minister Ed Balls is reading, Martin is offering up his time and expertise to help put a programme in place. "If the government want to get in touch, I'll gladly spend some time teaching teachers about this." Martin's website, www.MoneySavingExpert.com, is in the top 100 most-used websites in Britain, attracting around 3.7million individual users each month. More than 1.7million people also subscribe to the handy email he sends out, rammed with useful tips on saving money and finding bargains. "I used to go on Open House with Gloria Hunniford and write a column for the Sunday Express among other things," he says. "Setting up the website was a no-brainer for me. I actually set it up as a way to promote my broadcast work and so there was a place to back up information, but very quickly I realised it was going to be big. I never predicted it would be so big though - one in 10 adults in the country go on the site! "It's got to the point now where I've actually employed someone to go through the emails that are sent in to the website too. About 75% of those emails are people saying thank you for the advice, which they've used to get out of debt or financial hell."