Secondary 1 Math: Number Line and Negative Numbers

Secondary 1 Math: Number Line and Negative Numbers


by Jimmy Ling

Secondary 1 Math is very different from primary school math. Many of the methods which are taught in primary schools are not applicable in secondary schools anymore. Many students who did well for PSLE Math struggle in Secondary Math. If you did not do well for PSLE Math, do not be demoralised. As long as you understand the concepts and put in hard work in secondary schools, you will be able to do well.

To do well in Secondary 1 Math, you must be very clear with 2 concepts. They are

1. Negative Numbers

2. Algebra

We shall cover negative numbers in this post and cover some important rules when we deal with negative numbers.

The Number Line

number line

In a number line, the numbers on the right of zero are positive while the numbers on the left of zeros are negative.

As you move to the right, the number increases. On the other hand, if you move to the left, the number decreases.

Let’s compare between 1 and 2. Which number is bigger?

Obviously, the answer is 2.

Now, let’s compare between -1 and -2. Which number is bigger?

The answer is -1. Why?

From -1 to -2, the number moves to the left on the number line and hence, it decreases. The number becomes more negative and hence, smaller.

Addition and Subtraction

Once you have understood this concept, you need to learn how to do addition and subtraction which involves negative numbers. You should have learnt this primary schools. Let’s revise again for Secondary 1 Math.

What is 5 – 8?

Let’s illustrate on a number line below.

5 minus 8

 

We shall start from 5. Minus 8 means we move 8 spaces to the left. So the number will end at -3. You can imagine -3 as shortage of 3. If you have 5 balls and you need to give 8 balls away. You will have shortage of 3 balls.

Let’s look at another one.

What is -6 + 8?

negative numbers

We start from -6 first. Plus 8 means we move 8 spaces to the right. So we will end at positive 2. However, we do not write positive 2 as +2. We simply write as 2 which is positive by default.

In fact, if you are sharp enough, you may have realised that -6 + 8 is the same as 8 – 6. Yes, you can actually move the numbers around. But remember to bring the sign along! In this case, the minus sign belongs to 6. So when you move 6 to the back, the minus sign need to follow it.

Multiplication and Division

For multiplication and division which involves negative number, you need to memorise these 4 golden rules.

1. Plus × Plus = Plus

2. Plus × Minus = Minus

3. Minus × Plus = Minus

4. Minus × Minus = Plus

A good way to memorise this is when you multiply 2 numbers of the same sign, the result is always positive.

When you multiply 2 numbers of different signs, the result is always negative.

For example,

2 × 3 = 6

-2 × 3 = -6

-3 × 4 = -12

-3 × -4 = 12

The same rules apply for division as well!

4 ÷ 2 = 2

-4 ÷ 2 = -2

4 ÷ -2 = -2

-4 ÷ -2 = 2

You must know these rules at your finger-tips before you proceed to Algebra in Secondary 1 Math. When you reach Algebra, you will need to do lots of addition, subtraction, multiplication and division which involve negative algebraic expressions.

contributors

Bullying in Singapore – Do Things Improve after Victims Confide? [2.5]

Bullying in Singapore – Do Things Improve after Victims Confide? [2.5]

IMG_0526If you are being bullied at your workplace, will you confide in someone or share worth someone and hope things get better? If you don’t, do you expect your child to do the same?

Our students perceive the effectiveness of telling an adult or a figure of authority determines who they tell when bullied. However, many of them are under the perception that nothing can be done to improve the situation even after they tell someone.

Our students are perceptive enough to note 2 factors when they tell someone of a higher authority of their bullying: willingness and interest of adults to intervene on their behalf.

From the statistics, a good number believe that teachers are not all that ready to intervene on their behalf. Is that really true? We will be looking at that are in the next post.

bullying in singapore

Bullying in Singapore – Is Your Child Skipping School due to it? [2.3]

Bullying in Singapore – Is Your Child Skipping School due to it? [2.3]

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When bullying occurs in school, the victim does not feel safe and happy. This fear can cause the victim to skip school or play truant to avoid the bully.

When I conducted the latest parent-bonding session recently, a primary 5 student scribbled her thoughts furiously on a sheet of paper while sobbing. Before this session, the child has been loud and outspoken while showing slight disrespect to her peers and facilitators. The mom was a very soft-spoken lady who obviously loved her child very much.

Yet, it was soon discovered that the child was keeping many things within herself. She wrote that she thought of attempting suicide and to be with the ‘angels in heaven’. When probed later, it was discovered that she was bullied badly in school. Although she did not skip school, she was extremely frustrated with the way things were going. The biggest issue was that most parents and teachers tend to take action only when the child starts to skip school frequently. However, as statistics show – most victims actually continued as if it was part of their daily lives.

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Bullying In Singapore : Where has Bullying Happened? [2.1]

Bullying In Singapore : Where has Bullying Happened? [2.1]

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In the last post, we talked about how a study was conducted among primary and secondary school students on bullying in their schools. So, where does bullying normally occur? Do they differ in primary and secondary school?


 

RELATED: Research says You Child Plays a Role in Being Bullied


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The Primary school students reported that most bullying took place in areas such as canteens, school fields as well as classrooms. Most of the bullying tend to occur in the canteen. Interestingly, bullying in the school field happens more frequently than in Secondary schools.


 

RELATED: Overview of Bullying in Singapore: We Know it Exists [1/6]


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The Secondary students report that most bullying occured in the same areas – except bullying in classrooms tend to happen more often than most.

Some parents may ask –

“Why does it happen in the classroom? What is the teacher doing?”

“The canteen is very public. How come bullying can take place?”

Canteen

Most bullying tend to occur in the canteen during recess or after school. Some parents asked why so, especially since there are many students around at the same time. That itself is an issue. Most teachers prefer to avoid the canteen during the recess time or after school as there tend to be too many students milling around. Even when teachers are available in the canteen, unless they are delegated to patrol during recesses, most teachers will wound up chatting or having a quick meal.  When there are too many students crowding at the same time, interactions between student multiply. Between the hustle and bustle, one may not notice another student being bullied as most students are involved with their own matters.

Classrooms

Most bullying tend to occur in classrooms in Secondary schools during the transition between classes as well as relief periods. As students grow older, most bullies tend to be more assertive and confident of themselves in strengths and prowess. They are also able to assess the class management style of a teacher. Thus, most bullies are not afraid to act out in a teacher’s presence if they deem that they are able to get away with it. Furthermore, quick transition periods allow students to grab quick opportunities to hit out at someone.

(8)Teachers: The Key to Your Child’s Future [How to Select an Appropriate Secondary School]

(8)Teachers: The Key to Your Child’s Future [How to Select an Appropriate Secondary School]

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This is the last post of the series “How to Select an Appropriate Secondary School”

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Teachers are the key influencers on your child’s success in school. They are, technically, the frontline staff to develop your child’s  intellectual and emotional growth.  How these teachers are groomed and looked after are very dependent on the leadership, growth prospects and staff welfare provided.  If you come across a school where the turnover rate is high and they often have to utilise contract or adjunct teachers, you can be sure your child will definitely be a very likely victim of this arrangement and will affect the consistency of your child’s academic performance.

Contract/ Adjunct Teachers

While every school has a mix of contract and adjunct teachers, it may be good for a parent to find out their length of their stay and the positions they used to hold. Most of these adjunct teachers are former teachers who just resigned or older teachers who have left the service for quite some time. If some of the adjunct teachers are of a very senior age, find out the classes they are usually placed in charge in. Chances are, many of them will be given the N(T) classes and if that is so – discipline may be an issue.


RELATED: Your Insecurities may Cause Your Secondary School Child to Rebel


Staff welfare

Many teachers enter teaching due to passion and eventually leaves the service when their passion dies out due to overwhelming administrative work. Teachers are often given many responsibilities to juggle such as running of CCAs to planning and organising events to even conducting CCAs for some schools! Although it can be very difficult to find nowadays but a good school will try their best to balance the responsibilities and duties of their teaching staff so that they will have enough time to recharge, renew and to improve teaching strategies through self-reflection . If a principal proudly boasts of how much work their teachers are putting in, take caution and ask if ‘burn-outs’ or ways the teachers recharge themselves. If the programs organised for teachers by schools are often met with low participation levels, it may give signs that the teachers may be overworked.


RELATED: The Top 5 Insider’s Tips to raise a Happy Secondary School Child


Working Together

Lastly, a quick way to check if teachers are working together is to find out if standard materials or resources have been shared among the teachers while teaching the various levels. Some of you may ask – if all teachers have the same materials; won’t it display that the teachers are ‘slacking ‘ off as they do not personalised the materials? On the contrary, a standard set of materials should be developed and organised in folders so that the teachers are able to access them and use when necessary. The personalisation of materials to a class’ competency level comes under the discretion of the respective teachers with those sets.

If you ask around and find that different classes have different materials for a single subject AND level, it may be a sign that there is little guidance from the senior teachers in terms of material and resource development and teachers are not sharing their expertise and materials. There will be a lack of standardisation of assignments and ultimately, marks and performances.

 

This is the final post of the series. I hope they have been helpful for you.