This month's Bernard's Bag is really just a starting point for you to expand on with your children. The items, prices and promotions you choose to introduce can be altered to suit your class. If you do use it as it is, then printing off a copy is probably the easiest way for you to get an over-view of all the information.
Some of the learning objectives covered are:
Using mathematical ideas and methods to solve "real life" problems
Using and understanding vocabulary and notation related to money
Organising and using data
Choosing and using appropriate number operations and calculation strategies Explaining methods and reasoning
Making and investigating general statements
Suggesting extensions by asking "what if?"
Younger children would enjoy having shops set up in the classroom and being involved in role play. Using empty packets and cartons, along with plastic money or tokens, would be a good way in for many pupils. Another excellent resource would be flyers or leaflets from local supermarkets advertising their offers. (We would have used these ourselves but would get in trouble for copyright reasons!)

The maths behind this scene can obviously be differentiated accordingly, from basic practice using coins and exchanging, to applications of addition and subtraction. It is worth reading the article in Staffroom which gives sound advice on the introduction of money to children.

This investigation will stimulate a great deal of relevant discussion. Try to make the most of it! With only a small amount of exemplification, the children themselves should be able to suggest different scenarios which may affect where they would shop. This may lead into "what if?" type extensions, initially instigated by you but later by them too.

At a higher level, a more general approach can be taken, perhaps along the lines of consumer versus retailer benefits. You can open up the investigation further by splitting the class into groups and setting them off on a "shopping project" with certain aims and/or constraints.

It would be interesting to see whether this investigation gives children a different approach to shopping themselves or with their family!