ICT at key stage 3    (Year 7)

• Revise pupils' knowledge of spreadsheet techniques, including entry of data and formulae, graphing and modelling techniques. Use a prepared spreadsheet with column 1 being the items in a recipe for oatcakes, column 2 being the amount required to make enough oatcakes for four people and column 3 the cost of the item. Ask the pupils to investigate what happens when they change the values of any variable. Tasks for pupils could include demonstrating formulae building and replication to produce total costs for enough cakes for 8, 12 or more people. They could use an absolute cell to calculate costs and amounts for any variable, eg if the price of oats goes up or feedback from customers is that oatcakes are too sweet, too small.

• Discuss with pupils how the school tuck shop works, eg types and level of stock, amount of sales, costs and prices, what consumers look for in such a service, and what factors might have to be considered when running a tuck shop.
• Pool ideas on the purpose and nature of a successful school tuck shop and identify the constraints under which the shop would operate.
• Clarify the purpose behind identifying objectives (or end products), inputs and outputs for a system.
• With the pupils, identify and describe the rules governing the operation of a tuck shop. Present an outline of a model representing the changing inputs, differing constraints/variables that affect the outputs, eg a rush on an item could create disappointment, a rise in price could affect sales. Finally, explain that one use of the model will be to predict trends and outcomes.

• Ask pupils to start building a model of the tuck shop, translating the rules into formulae - all pupils will model the same agreed tuck shop, eg limited products, agreed time for model. Pupils should save versions of their model in order to describe its evolution when evaluating its success.

• Ask pupils to continue building a model of the tuck shop, translating the rules into formulae.
• Ask the pupils to test the model with sample data to investigate a variety of scenarios, eg a heatwave resulting in the need for a larger stock of cold drinks.
• Ask the pupils to produce a report on the tuck shop at the end of the agreed time, using software that allows them to combine text, tables and graphics.