2.6 Mass  (Page 2/3)

Seeing that 3x and ÷ have just been done, it is easy to introduce thirds now. Give the learners loose paper shapes and allow them to fold and measure on their own, so that they can discover how it can be done. Some of the learners will know how to find sixths without any help. (Only enrichment)

The idea with the recipe is to make the learners understand that certain standard units and containers must be used, otherwise there is no chance of success with a recipe.

Let the learners mention more examples of the use of standard units in practice, e.g. petrol, milk, mixing medicines, prescriptions for administering medication, etc.

It is essential that all the different standard measuring containers and scales, as well as sand, water and objects used in measuring volume and mass , should be available in the classroom. Learners should be able to experiment every day with measuring and weighing, using standard units: litres and millilitres and grams and milligrams .

A bathroom scale is required to determine the mass of the learners.

Different methods are used for the multiplication and division calculations, but should you prefer another method and you find that the learners understand it better, it is their right to use the preferred method.

It is essential that many similar examples of the relevant number sentences be done orally before the learners are expected to complete this worksheet.

The regrouping of a hundred when adding or subtracting is now formally taught. Sufficient concrete work must be done beforehand. More advanced work where a ten and a hundred are regrouped simultaneously, should not be done at the same time. It will depend on the abilities of the group whether it should be done immediately hereafter or at a much later stage.

Whether the learners will be allowed to make use of carried numbers, remains the decision of the educator. e.g.

Learners will need a blank sheet of paper in order to calculate the shortest route. Some learners may find it difficult and may want to give up, but with a little help they should be able to do it.

A discussion on what they will see as they approach the farmstead by road is necessary before the learners will be able to draw it.

Leaner section

Content

Activity: mass [lo 1.8, lo 1.9, lo 2.2, lo 4.5]

• Bonny and Granny want to make some pancakes. If they want the pancakes to be a success, they have to measure the ingredients accurately .

Dry ingredients such as flour and sugar are measured in grams and kilograms . A standard measuring cup and standard measuring spoons are used. You may use a kitchen scale to weigh the ingredients. Remember: 1 000 g = 1 kg

Liquids such as oil, milk and water are measured in millilitres and litres , and a standard measuring jug and measuring spoons are used. Remember: 1 000 m ℓ = 1 ℓ

• Here is their recipe. Why don’t you try it out at school or at home

Ingredients:

4 cups (544g) cake flour

4 eggs

1 cup (250mℓ) oil

1 t (5mℓ) salt

¼ cup (63mℓ) vinegar

1ℓ water

4 t. (20mℓ) baking powder

Method:

1. Beat the eggs, oil, vinegar and a little of the water very well.