Currently, I am teaching the topic on time.

We are beginning to teach pupils how to draw timeline instead of writing 2.30 pm + 30 mins = 3 p.m. I have reminded my pupils why 2.30 pm + 30 mins = 3 p.m. because a specific time cannot be added to duration. Despite going through in detail in class, I was surprised that some of my pupils were still writing the number sentence 2.30 p.m. + 30 mins = 3 p.m. though they drew the number line as well.

Moreover, their number line were not very helpful. It is obvious that that they had worked out the answers mentally in their heads.

Why is my pupils still writing it incorrectly?

Primary Three Teacher

This could be due to some of them being given extra (incorrect) instruction at home. The fact that the incorrect number number sentence give them the correct answer does not help your cause either.

It is good you tell them it is wrong. But be prepared for some who will take a longer time to represent the ideas correctly. Continue with the time line representation.

I am glad you pointed out that a point in time (e.g. 2 p.m.) cannot be added to time duration (e.g. 2 hours). Some students are taught by adults who make this mistakes themselves.

Fractions

A few colleagues and I realise that our pupils have difficulty comparing fractions such as 2-sixths and 2-tenths. We provided alot of visuals such as fraction chart but the pupils are still confused. In My Pals Are Here! Primary 2, pupils are required to compare fractions such as 2 sixths, 4 sixths vs 2-sixths and 2-tenths.

They are confused between the concepts. Some can compare 2 sixths ad 4 sixths very well but not being able to compare 2-sixths and 2-tenths.

While others confuse the 2 methods involving the two tasks and end up with 2 sixths is bigger than 4 sixths while 2-sixths is smaller than 2-tenths.

How can I help our pupils overcome it?

Teacher in Singapore

If students are making mistakes such as 2 sixths is larger than 4 sixths then they are not making connections to visual representations. You should always use visual representations in early stages of learning fractions.

Early instructions in fractions is critical. Students should be well taught throughthe use of manipulatives and visuals that when 1 is divided into equal parts, the parts are named according to the number of parts. When 1 is divided into six equal parts the parts are each called a sixth, for example.

This allows them to reason the relative sizes of say 1 tenth and 1 sixth.