2. Adding and subtraction with fraction strips
In this part, we build on the previous work with fraction strips to add and subtract simple fractions.
As you work, ask yourself these questions:
Are you having to help your pupils a lot? If so, why do you think this is?
Are you and the pupils enjoying the practical activities?
Do you think the pupils learn more this way than if you had just told them? How do you know this?
Case Study 2: Further work with fraction strips
Mr Agbe brought to his lesson a large fraction strip of tenths that he had made and asked each pupil to make a similar one using the resources he provided. After 15 minutes, he helped pupils use their fraction strips to find answers to these questions:
By how much is 8/10 bigger than 5/10?
What is the difference between 8/10 and 5/10?
What is 8/10 - 5/10?
He wrote on the chalkboard the sum 8/10 - 5/10 = 3/10 and asked the pupils to copy this in their exercise books.
He then asked his pupils to work in pairs and do some addition sums with tenths using their fraction strips. He made up some sums for them, and then asked those who were working well to make up some sums for each other.
Mr Agbe was amazed at what the pupils were able to do, but also realised that he needed to give some pupils more practice and time to talk about their ideas as they worked.
Activity 2: Adding and subtracting simple fractions
Before the lesson, prepare three discs – a complete disc, a quarter disc and a half disc, each with all the quarters shown (see Resource 4: Fraction discs).
Hold up the quarter disc and the half disc and ask your pupils what would be the total if you added these two discs. Give them time to answer, and when you get the right one, write the sum on the board: 1/4 + 2/4 = 3/4
Next, hold up all three discs and ask what would be the total if they were all added together.
Again, wait for the right answer and then write the sum on the board: 1 + 1/4 + 2/4 = 1 3/4
Now pair your pupils, and ask them to draw similar discs with thirds. Ask them to make up addition sums to give to their partner and to write down the complete sum and answer in each case.
As they are working, go around the class and help where needed. If necessary, let them try other fractions to see if they really understand the idea.
Display some of the different fractions on the wall.
You may want to do this activity over two lessons to consolidate pupils’ learning.