Current Affairs 3rd Class

LEARNING OBJECTIVES

• Know about money and its use
• Learn various denominations of money and coins used in India.
• Analyze situations to enable addition, subtraction, multiplication and division of money.
• Enable a child to count the money.

  REAL LIFE EXAMPLES

• People make budget for their money. Budget means to plan before hand how and where to spend money.
• People save money in banks or invest for future.
• People collect coins and notes of older times.

This lesson will help you to:-   HISTORICAL PREVIEW

• In ancient days before money was invented, the barter system was used.
• Barter is a system where people used to exchange their products with each other because they didn’t have money that time.
• The history of the rupee traces back to 15th century, when the first “rupee” is believed to be introduced by Sher Shah Suri (1486-1545)

  QUICK CONCEPT REVIEW

• What is Money? Money is any object or record that is generally accepted as payment for goods and services.
• Money is also known as currency.
• The unit of currency in India is Rupees which is denoted by following symbol: Rs.
• Other important currencies in the world are USD $ (United States Dollar which is used in America), GBP (UK Pound Sterling £) used in United Kingdom and Euro used in Europe.
• Money in India comes in form of paper as well as coins.
• 1 Rupee = 100 paisa

10 coins of 10 paisa make one Rupee. 2 coins of 50 paisa make one Rupee. 1 coins of 25 paisa make one Rupee. 1 coin of 50 paisa and 2 coins of 25 paisa make one Rupee.  

• The paper based notes available in India are of

Rs. 1000, Rs. 500, Rs. 100, Rs. 50, Rs. 20, Rs. 10, Rs. 5 as shown below:  

• Till few year back there were paper notes for Rs. 2 and 1 as well but they are no longer in use but are still valid. Their picture is as shown below:

 

• The coins available in India are of Rs.10, Rs.5, Rs.2, Rs.1, 50p and 25p as shown below;

AMAZING FACTS

• Paper notes are called bank notes as they are issued by the Reserve Bank of India (RBI)
• Coins of 50p, 25p and 10p are not in use in many parts of India but still there are few towns/cities where they are being used.
• Picture of Mahatma Gandhi, father of the nation, is printed on every note
• Every note contains signature of RBI Governor
• As the value of currency increases, the size of the paper note also increases.

  MISCONCEPT/CONCEPT Misconnect: If a paper note is mutilated or torn, then you feel that it cannot be used as no shopkeeper is ready to take it. Concept: Torn or spoilt notes more...

LEARNING OBJECTIVES This lesson will help us to:-

• Define fractions numerator and denominator.
• Identify a fraction using object and shapes.
• Understand equivalent fraction.
• Compare fractions.
• Add unit fractions with like denominators.

  REAL IF EXAMPLES

• An hour is divided in fraction of hours. Half\[\left( \frac{1}{2} \right)\] and hour; quarter of an hour.

.

• Sport like football, have half time in the game. Half time shows a break marking the completion of half of a game.

  QUICK CONCEPT REVIEW When a whole object or group is divided into equal parts, then each part is called a fraction of that whole. Suppose, there is an apple and you want to divide it equally among 2 friends then equal pieces of the apple form fractions. A fraction is a part of a whole divided in equal parts.   PROPERTIES OF FRACTION

• A fraction is written in the form of \[\frac{N}{D};D\ne 0.\]Here N is called the numerator and D is called the denominator. For example; \[\frac{1}{3}\] means one part out of 3 equal parts.
• When a whole is divided in 2 equal parts, then each part is called a half and is written as\[\frac{1}{2}\]

• When a whole is divided in 4 equal parts, then each part is called quarter or one-fourth and is written as \[\frac{1}{4}\].

• Fractions that appear differently but have the same value are called equivalent fractions. For example \[\frac{2}{4}\] ,\[\frac{1}{2}\]and\[\frac{3}{6}\].

• In a fraction, multiply the numerator and denominator by the same number to get an equivalent fraction.

For example: \[\frac{1}{4}=\frac{1}{4}\times \frac{3}{3}=\frac{3}{12}\] So, \[\frac{1}{4}\] and\[\frac{3}{12}\]are equivalent fractions.   TYPES OF FRACTIONS Let us now understand different kinds of fractions. Fractions can be divided into two categories:

Like and unlike fractions.

Proper and Improper fractions.

Like Fractions are those fractions which have the same denominators. \[\frac{1}{9},\frac{2}{9},\frac{3}{9},\frac{5}{9},\frac{6}{9}\]Etc. is all like fractions Unlike Fractions are those fractions which have different denominators. \[\frac{1}{3},\frac{2}{13},\frac{4}{9},\frac{5}{8},\frac{6}{11}\] are all unlike fractions. Proper Fractions are those fractions in which the numerator is less than the denominator. \[\frac{1}{2},\frac{2}{3},\frac{4}{5},\frac{6}{7},\frac{8}{9},\frac{9}{11}\]are all proper fractions. Improper Fractions are those fractions in which the numerator is greater than the denominator, \[\frac{3}{2},\frac{8}{5},\frac{7}{4},\frac{12}{10}\] are improper fractions.   Games Take paper cut outs of basic shapes like circle, square and rectangle. Now fold the paper to get equal parts. It's time to cooer. Color half quarter, one third of different shapes   HISTORICAL PREVIEW

• The egyptions were one of the first groups to study fractions. It evolved from problems like division of food as there was no money to make payment.
• The arabs introduced the fractional bar in the 12th century

  AMAZING FACTS

• The word fraction is originated from a Latin word fraction, which more...

LEARNING OBJECTIVES This lesson will help you to:

• recognize division as equal sharing.
• understand the concept of division as equal grouping.
• prepare division facts by using multiplication tables.

  Real life Examples

• When you are a eating a birthday cake, you have to make equal shares of the cake, so that everyone gets their share. For this you divide the cake in equal sizes.
• If you have Rs. 20 and you want to buy chocolates and each chocolate is of Rs. 5. By using the method of division you can find out the number of chocolates you can buy. Since, 20 ÷ 5 = 4 so you can buy 4 chocolates.

  DIAGRAMS/PICTURES There are 12 daisies. Make groups of 3. I How many groups do you get? How many 3's are in 12? The answer is 4. So. 12 - 3 = 4. The symbol'\[\div \]' indicates Division. Think: If you DIVIDE 10 into groups of two, how many groups are there? How many groups of two are there in 10? How many two’s are there in 10? Since 2+2+2+2+2= 10, there are FIVE twos in 10; 10 \[\div \] 2 = 5 Division is the equal distribution of a given quantity. The number to be divided is called the dividend. The number which divides is called the divisor. The answer is called the quotient. The number left after the division is called the remainder. Chunmun bought 15 apples from fruit market. She placed 15 apples equally in 3 baskets. Divide 15 into equal groups. There are 5 apples in each group. Therefore, 15 - 3 = 5 1. Mrs. Khanna got 35 flowers on her wedding anniversary. She placed them equally in 5 vases.   There were 7 flowers in each vase. So, 35 - 5 = 7 or "Thirty five divided by five is seven." 2. Minki arranged 32 glasses on the dining table for guests.   Amazing Facts

• If you make groups of 1 then the answer is number itself because any number divided by 1 is the number itself. For example, 4 ÷ 1 more...

LEARNING OBJECTIVES This lesson will help us to:

• Recognize multiplication as repeated addition.
• Explain the concept of multiplication as repeated addition.
• Identify the sign of multiplication.
• Construct the multiplication tables of 2, 3, 4, 5 and 10.
• Write multiplication facts for 2, 3, 4, 5 and 10.
• Use the multiplication facts in various situations.

  REAL LIFE EXAMPLES

• If you want to buy 5 dozens of eggs and each dozen contains 12 eggs, then you need to multiply 5 and 12 which is 5 X 12 = 60 So, you can calculate the total number of eggs in 5 dozens.
• If you are going out on a picnic and you have 3 cars with you and 5 people can sit in each car then you need to use multiplication skills to calculate the total number of persons that can go for picnic i.e. 3 X 5 = 15 persons.
• While celebrating your birthday party, you want to decorate your room with balloons and you want to place 8 balloons on each wall and there are 4 walls in a room, then you need to multiply 8 and 4 to find out the total number of balloons you need to buy i.e. 8 X 4 = 32

  QUICK CONCEPT REVIEW Multiplication is repeated addition. The number to be multiplied is the multiplicand, the number we are multiplying with is the multiplier and the result is called the product of multiplication. Examples 1.  This is a flower. It has 8 petals. How many petals are there in 5 such flowers? 8+8+8+8+8= 40, or 5 times 8 = 40, Or 5 x 8 = 40 2.  This is an ant. It has 6 legs. How many legs do 7 ants have altogether? 6+6+6+6+6+6+6= 42, or 7 times 6 = 42. Or 7 X 6 = 42 3.   This is a tray with Ladoos (sweet). It has 9 Ladoos. How many Ladoos are there in 6 trays? 9+9+9+9+9+9=54, Or 6 times 9 = 54, or 6 X 9 = 54   MULTIPLICATION TREE 10 \[\Rightarrow \]1X 10 =2X5=5X2 35 \[\Rightarrow \]1X 35 =5X7=7X5 24 \[\Rightarrow \]1X24=2X12=3X8 more...

LEARNING OBJECTIVES This lesson will help you to:

• Understand the concept of subtraction using a 10 x 10 grid.
• Subtract using 2 digit numbers.
• Subtract using 3 digit numbers.
• Apply subtraction to real life situations.

  Real life Examples

• Elevator is a real life example of addition and subtraction. The ground floor is considered to be 0.
• Subtraction helps in calculating the amount left in bank account after debits.

  AMAZING FACTS

• Subtract is formed by two words “sub” and “tract”. “Sub” means “below” and “tract” means “to pull away”.
• When we subtract zero from a particular number (or digit of a number) we get the number (or the digit) itself. For example: 413-100=313

  QUICK CONCEPT REVIEW Subtraction is taking away a certain number of objects from a bigger set of objects.   MORE ABOUT SUBRTACTION

• Subtraction is one of the basic four operations.
• It is denoted by the symbol “-“. For example: 12 subtracted from 45 can be written as 45-12.
• The number of items left after subtraction is called “difference”.
• A 10 x 10 number grid is a helpful tool to subtract 2-digit numbers.
• Some words that denote addition are "minus", "take away" and "left",
• Addition can be done in different ways
• Counting in tens: 47- 34 = 47 - 10 -10-10-4
• Place value: 56 - 13

6 – 3 = 3 50 - 10 = 40 40 + 3 = 43   HISTORICAL PREVIESW

• The plus and minus symbols were in use before they appeared in print. For example, they were painted on barrels to indicate whether or not the barrels were full.
• To make subtraction easier it is important to regroup the numbers.

For example: 781 - 676 Subtract the ones = 11 - 6 = 5 Subtract the tens = 70-70=0 Subtract the hundreds = 700 - 600 = 100 100 + 5 = 105   MISCONCEPT/CONCEPT

• Misconcept: Subtraction is commutative.
• Concept: Subtraction is not commutative. For example:

18-13 is not equal to 13-18   PLAY TIME:

• Pick up a 3 digit number. Mix the digits of the number and form a new 3-digit number. Subtract the smaller number from the bigger number.

Learning Objectives This lesson will help you to:

• Understand the concept of addition using a 10 x 10 grid.
• Add using 2 digit numbers.
• Add using 3 digit numbers.
• Apply addition to real life situations.

  Real Life Examples

• Addition helps in calculating the money spent for buying commodities from the market.
• Addition helps in calculating measurements like distance

  AMAZING FACTS

• The opposite sides of a dice always add up to seven.

  Quick concept Review Addition is combining smaller sets to a bigger single set. Facts of daily life help us in understanding the concept better.     More about Addition Addition is one of the basic four operations.

• It is denoted by the symbol"+". For example: 4 added to 9 can be written as 9 + 4.
• The numbers that are added are called addends.
• A 10 x 10 number grid is a helpful tool to add 2-digit numbers.
• Some words that denote addition are "in all", "total", "sum" and "altogether".
• Addition can be done in different ways s

        Counting in tens: 55 + 23 = 55 + 10 + 10 + 3 = 75 + 3 = 78

• To make addition easier it is important to regroup the numbers.

        For example: 421 + 379 Add the ones = 1 + 9 = 10 Add the tens = 20 + 70 + 10 = 100 Add the hundreds = 400 + 300 + 100 = 800 Add 800 + 100 + 10 = 910 Similarly for four digit numbers first of all add one digits, then tens, then hundreds and then thousands respectively.   PROPERTIES OF ADDITION

Commutative or Order Property of Addition: Two or more than two numbers can be added in any order

e.g.

• 290 is same as 1290 + 2130.

Associative property of addition: Sum of three or more number is not affected by their grouping e.g.

1200 + 1400 + 1300 = (1200 + 1400) + 1300 or 1200 + (1400 + 1300).

Sum of zero (0) and number is the number itself. This zero is called identity element e.g. 7000 + 0 = 0 + 7000 = 7000.

  HISTORICAL PREVIEW

• The ‘+’ and ‘-‘symbols first appeared in print in more...

Learning Objectives This lesson will help you to read:—

• understand even and odd number.
• understand ascending and descending order.
• know about place value, face value expanded form of numbers and number names.
• learn about smallest and largest number.
• understand skip counting.

  Amazing Facts Zero (0) is the only number which cannot be represented by Roman numerals. Abacus is considered the origin of the calculator. While writing number names from 0 to 1,000 the letter “A” only appears in 1,000 (‘’ one thousand ’)   Quick Concept Review Even and odd Numbers

• Numbers which are divisible by 2 are called even numbers. Examples: 2, 4, 6 etc.
• Numbers which are not divisible by 2 are called odd numbers. Examples: 3, 5, 7 etc.

  Ascending and Descending Numbers

• Arranging numbers in ascending order means arranging them from smaller to greater.
• Arranging Numbers in descending order means arranging them from greater to smaller.
• Let the series of numbers be 30,12,18,17, 22, 48, 40, and 28.
• Ascending order of these numbers is 12, 17, 18, 22, 28, 30, 40, 48
• Descending order of these numbers is 48, 40, 30, 28, 22, 18, 17, 12

  Place Value The value of a digit due to its position in a number is called its place value.

Ten thousands	Thousands	Hundreds	Tens	Ones
10000	1000	100	10	1

  For example if we have to place 87654 we will show it        

Ten thousands	Thousands	Hundreds	Tens	Ones
8	7	6	5	4

    Face Value Face value of a digit in a number is the digit itself. For example- Face value of 9 in 1892 is 9. more...

LEARNING OBJECTIVES This lesson will help you to:-

• know about resources
• identify and understand renewable resources
• identify and understand non-renewable resources
• learn how we can save resources

  QUICK CONCEPT REVIEW You already know about living things and their needs. You also know that in order to survive, living things need food, water and air. We need different things in our daily life, which are made up of different materials, for example we breathe in air, we cook food with the help of water, grains, cereals, spices, vegetables and LPG (fuel). Resource is defined as a substance or object required by a living organism for normal growth and main tainence. All the things which we use are categorized as Renewable and Non-renewable Resources.   WHAT ARE RENEWABLE RESOURCES? The resources which have the ability to renew themselves are called renewable resources. That means they will be always available to us as they keep on generating. They can never get used up. Let us discuss them one by one and see how we use them.   WATER We all need water to survive. Apart from drinking water we use water in many activities like farming, cleaning and cooking food etc. We cannot survive without water. Even plants and animals also need water to survive. Sources of water are lakes, wells and rivers etc. and most importantly rain. We can get water resource from We should not waste water. It is very valuable for all the living things. While using water we should keep following things in mind:     

• Always turn off the tap when not in use.
• Never throw away water.
• Repair a leaking tap or a leaking pipe.

As the population is increasing we need more water and we need to conserve it. Like other renewable resources we have it in plenty but we will have to control the wastage so that in coming years we can meet with our need of water. With more industrialization we are contaminating our water resources by throwing waste chemicals in them. Washing of clothes and bathing of animals in pond should also be stopped to keep the water resources clean.   SOIL: Soil or earth is also a renewable resource. We live on it. It supports the trees and gives us shelter. Below earth's surface there are sources of water. The land also provides us with minerals like copper and iron etc. We should try not more...

LEARNING OBJECTIVES This lesson -will help you to:—

• understand how pottery was invented.
• understand how clay is used in making different things.
• understand why it is necessary to bake the clay pots.
• observe the diversity in different types of clothing.
• study different colours and designs used in various types of textiles.
• know how fire was invented and how we use fire in our daily life.

  Interesting Facts

• The potter’s wheel was invented in Egypt around the year 3000 BC
• High Fired ceramics, like stoneware and porcelain, were first produced by Chinese culture
• Silk is obtained from the cocoons of silk worms, and is harvested by dipping the cocoons of silk worms, and is harvested by dipping the cocoons in hot water and unwinding it. It is then spun silk culture has been practiced for at least 5000 years in china. A silkworm’s diet consists mainly of mulberry leaves.

  POTTERY The term "pottery" refers to any type of ceramic ware that is made from clay and hardened by fire. Pottery making is the process of turning raw clay into a bowl, plate, cup, pot or other vessel. The art of making pottery began as early as 6000 B.C. and was used to keep important things of everyday life. In the beginning pots were made of stone and clay. Earlier people used to make pots of clay by kneading the clay and shaping them with their hands. Later discovery of potters wheel made it easier to make pots. As time passed, the potter's wheel became better and better. Today electric wheel is used which has made pottery making much faster. People also discovered that they can make the clay pots harder by baking them. A kiln is a kind of oven in which pots are placed to bake. Pots are heated at very high temperature and taken out only when they are cool.   POTTERY VESSELS WERE CREATED

• To store and cook food.
• To gather and transport grains, berries and nuts.
• To carry water.                                
• To have food in it.
• Later, pottery evolved as an* art form, with pictures being shown on the vessels to share stories.
• In modern times pottery pieces are used as decorative accents, dinnerware, vases, and other useful items.

  VARIOUS STEPS INVOLVED IN POTTERY 1. Kneading clay 2. Making pots 3. Baking the pots in kiln 4. Decorating Pots 5. Selling different pottery more...

LEARNING OBJECTIVES This lesson will help you to:-

• learn about motion.
• learn about factors that causes a body to be in motion.
• study different types of motion.
• learn about uniform motion, non-uniform motion and circular motion.

  Real Life Examples

• When a baseball player runs around the bases, his or her position changes, which shows that motion is performed.
• When you switch on the fan it starts moving in a circular motion.

  Historical Preview

• Sir Isaac Newton was the one who first thought about the reason why all objects fall down and found the actual reason behind it. He said that gravitational force causes every object to come down. He later found the relationship between force and motion and introduced the three laws of motion.

  QUICK CONCEPT REVIEW The world is filled with movements. Some movements (motion) just happen. The earth revolves around the sun, snowflakes fall to the grounds etc. Some motions we can control, like we walk, pickup things, play etc.   MOTION

• Motion is a state of change. It is an act, process or instance of changing place.
• It can be a movement caused by nature or a change of location or energy created by manmade means.
• For example when we move our legs to walk, we are putting them in motion.
• Whether the movement is of a planet revolving or you playing a game, the motion happens because of force.

  FORCE AND MOTION

• When we push or pull something, we are using force to try to move it or put it into motion.
• For example pushing a table. Pulling a door. Walking etc.

  TYPES OF MOTION There are three types of motion viz. Uniform motion, non-uniform motion and circular motion.   Uniform Motion A body is said to be in uniform motion if it covers equal distance in equal interval of time. For example:

Planets move around the sun in uniform motion.

Suppose a bus travels at a constant speed of 73 miles per hour. Then this constant speed can be called as uniform motion.

Non- Uniform Motion                      

• When a body covers unequal distance in equal interval of times or vice- versa, then the body is said to have non-uniform motion.
• For example a racing horse, swing.

more...