2.6 Mass

Mathematics

Bonny and tommy visit the farm

Educator section

Memorandum

• Number Concept to 600
• Operations:
• Addition – two and three digit numbers with and without regrouping of the ten.
• Subtraction – two and three digit numbers with and without regrouping of the ten.
• Multiplication – two digit number with a one digit number without regrouping the tens to 99.
• Division – two digit numbers divided by a one digit number without a remainder or regrouping the tens to 99.
• The 3× and 3÷ tables to the tenth multiple are taught. These conclude the tables to be learnt in Grade 3. Repetition and testing should be done regularly.
• The telling of time is very important. It is recommended that this be done classically as it requires much preparation and is immensely time consuming.

The learners each need a clock to handle and can construct one out of cardboard before the lesson.

In module 4 the number concept is extended to 600. Addition and subtraction calculations include two and three digit numbers. Multiplication and division calculations are done without regrouping of tens, and only up to 99.

In learning 3x and ÷ up to the 10th multiple, the tables that have to be mastered in Grade 3 are completed. Regular repetition and testing are vitally important from this stage on.

It is recommended that the reading of time be done with all the learners at the same time. Each learner must have a cardboard clock to use when the work is being done.

Such a clock can be made from a paper plate, or the learners can be allowed to design their own clock for Technology. However, it must be ready before the reading of time is started in class. A great deal of practical exercise is necessary before the learners can complete the worksheets.

Number concept is now extended from 400 to 600 and the number blocks of hundreds, tens and units, as well as the flared cards, (attached to Module 2), must still be used to promote the number concept. Give special attention once again to the 100 that must be regrouped when 300 and 500 are halved: 300 = 200 + 100 500 = 400 + 100

Counting in sixes must be done incidentally and can also be repeated on the multiples chart (Module 2). Learners must know: 1 dozen = 12 .

Learners must have the opportunity, and be encouraged, to say what they can deduce from the graph, what can change and what will not change, before they have to write about it. Such a discussion will give you a good indication of what the learners understand and which aspects need more attention.

Learning 3x and ÷ must be done on the mat and with the use of concrete apparatus. The worksheets are only there to apply what has already been taught.

Learners must get the opportunity in class, on a daily basis if possible, to take measurements with the ruler, the metre stick and the trundle wheel. The more practice they get, the more accurately they will measure. However, always encourage them to estimate first .

This is enrichment work and if you find that it is too advanced, it can be done at a later stage. There may be learners who would like to accept the challenge.