Do free school meals work?

All pupils at infant schools in England are to get free school lunches from next September, but does the evidence prove free dinners improve results? 'I accept every time I get in my car, there's a 20% chance I could die' - it's a line from the Formula 1 hit film, Rush, but was it really true for 1970s racing drivers? The government wants shops to start charging for plastic bags and the Deputy Prime Minister Nick Clegg says a plastic bag takes 1,000 years to degrade, but More or Less finds the environmental facts about plastic bags are much less certain than that statistic suggests. And do the health benefits of cycling outweigh the risk of injury? Professor David Spiegelhalter goes through the numbers.