What a shame that +Plus magazine is suggesting that confidence-building and efficient computation techniques are 'faffing'.

Students who know their times facts (times tables) have no difficulty finding LCM, those with less confidence can try the ' 2x bigger denom, does it work for smaller? 3xbigger denom, does it work for smaller' method. Those who find LCM an issue would be better if given activities and time to understand the LCM concept and build instant recall skills in times facts. If LCM is beyond them, using bigger CMs just gives more opportunity to make computation errors with the bigger numbers - not a confidence-building approach.

Fractions techniques are brilliant tools to simplify otherwise complex calculations. Fractions are already short-cuts for multiply/division. I teach them as a step into using 'professional tools' as you would teach an apprentice the techniques of the master craftsman.