Course

Primary Mathematics: foundations

Name: Primary Mathematics: foundations
Price: 1399 BDT

Primary maths you do, not maths you read. Every lesson gives your child something to move, a guess to make first, and one idea to keep. Built for English-medium students aged 9 to 11.

63 lessons5h 32mEnglish

What you'll learn

Read, write and compare numbers up to four digits, and say what each digit is worth
Add and subtract across a boundary like 100, and check the answer by working backwards
Know the times tables, and find factors, multiples, the HCF and the LCM
Compare fractions, find a fraction of an amount, and share in a ratio
Work with decimals, taka and paisa, a shop bill, a bus fare and a percentage
Measure perimeter and area, estimate an area by counting squares, and reflect a shape

Requirements

Able to count, read and write numbers to 100
Knows addition and subtraction facts within 20

Course content

63 lessons · 5h 32m

Place value, and how big a number is

What each digit in a number is worth, why nine and one more makes the next wheel turn, how the same digits can mean different amounts, rounding to the nearest ten, and counting on in tens.

0/12

What each digit is worth

The 4 in 3407 is worth 400, because of the place it sits in.

Preview5m 2.

Nine and one more: the carry

A wheel cannot hold ten. It drops to zero and pushes the wheel on its left.

Preview5m

Same digits, different value

407 and 470 use the same three digits, and one of them is bigger.

Ten notes make a hundred taka

Ten of one thing makes one of the next thing, in money and in every place.

Rounding to the nearest ten

Count the steps to each ten. 17 is three steps from 20, so it rounds to 20.

Counting on in tens

Add ten each time and only the tens digit changes.

What happens when you multiply by ten

Every digit moves one place to the left and a zero fills the ones place.

A pattern that adds ten every step

The counts 15, 25, 35 follow the rule 10n + 5, so the sixth count is 65.

Lakh, crore and million

One crore and ten million are the same number. Only the name and the commas change.

10.

A robot counts in twos

Every switch is on or off, so a robot writes thirteen as 1101. A base is a choice about how many digits you allow.

11.

Which row rolls fastest

One count drives four bases at once. The smaller the base, the more often its last digit turns over.

12.

Check what you know

Three questions on digit value, rounding and multiplying by ten.

Adding and subtracting, including across 100

Adding as a jump forward, subtracting as a jump back, how to cross a boundary like 100 without losing a ten, finding a missing part, and checking your answer by adding it back.

0/9

Adding is a jump forward

From 8, a jump of 7 lands on 15. The line shows the whole jump at once.

Preview5m 2.

Add the tens first, then the ones

To add 33 to 56, move the tens wheel three times and the ones wheel three times.

Preview6m

Crossing one hundred

Split the jump at 100. From 96 go 4 to reach 100, then 4 more to reach 104.

Subtracting is a jump back

From 113 a jump back of 15 lands on 98, and 100 is a good place to stop.

Weighing a part you cannot see

Add ones until the two pans match, and the hidden amount is the count you stopped at.

The missing number in a sum

45 plus something is 72. Balance the two sides and the missing number is 27.

Adding nine the quick way

Add ten, then take one back. It is faster and the answer is the same.

Six runs in every over

Start at 12 and add 6 each over. Repeated adding is what multiplying does.

Check what you know

Three questions on adding across 100, subtracting back, and a missing part.

Times tables, factors and multiples

Multiplying as equal rows, finding the rule of a times table, what a multiple is, sharing equally as division, and using two circles to find the factors and multiples that two numbers share.

0/9

Rows of four: a times table you can see

Each new row adds four chairs, so the counts go 4, 8, 12, 16 and the rule is 4n.

Preview5m 2.

Predict the total before you count

Two rows tell you the rate. From there you can predict five rows without counting.

Preview6m

Find the times table

One matching pair is never enough. Test every pair before you name the rule.

Multiples: the numbers you land on

Count in sixes and every number you land on is a multiple of 6.

Sharing equally is dividing

Six equal bags balance 24 weights, so each bag holds 4 and 24 divided by 6 is 4.

The missing factor

Five equal rows hold 40 chairs. Balance the sides and one row holds 8.

Factors that two numbers share

12 and 18 share the factors 1, 2, 3 and 6, so their highest common factor is 6.

Multiples that two numbers share

Fours and sixes both land on 12, 24 and 36, so the lowest common multiple is 12.

Check what you know

Three questions on multiplying, factors and the lowest common multiple.

Fractions: what they are and how they compare

A fraction as equal pieces of one real thing, what the numerator and the denominator each tell you, two names for the same amount, a fraction of a quantity, sharing in a ratio, and comparing fractions out of a hundred.

0/9

The two numbers in a fraction

The denominator says how many equal pieces. The numerator says how many you took.

Preview5m 2.

More pieces means smaller pieces

One eighth is smaller than one quarter, even though 8 is bigger than 4.

Preview5m

Two names for the same amount

Cutting every quarter in half gives eighths, and three quarters becomes six eighths.

One third of a plate

Three equal shares balance 18 pithas, so one third of 18 is 6.

A quarter of twelve pithas

A quarter is 25 out of every 100, and a quarter of 12 pithas is 3.

Sharing a plate: how many of each

One part to two parts means three equal parts, so 12 pithas split into 4 and 8.

Comparing two fractions fairly

Three quarters is 75 out of 100 and seven tenths is 70, so three quarters is more.

A machine that takes a quarter

Finding a quarter of a number is the same as dividing it by 4.

Check what you know

Three questions on comparing fractions, equivalent fractions and sharing.

Decimals, money and measuring

Tenths and hundredths on a measuring strip, why 0.4 and 0.40 are the same amount, comparing two decimals fairly, a shop bill line by line, change from a note, a bus fare with a starting charge, and a percentage off.

0/9

Tenths: one metre cut into ten

Three tenths of a metre is 30 cm, and it is written 0.3 m.

Preview5m 2.

Why 0.4 and 0.40 are the same

Four tenths and forty hundredths shade the same length, so the amount is equal.

Preview6m

Which is more, 0.5 or 0.45?

Count both in hundredths: 50 beats 45, so 0.5 is the larger measurement.

A shop bill, line by line

Each line is quantity times unit price. The usual error is forgetting the quantity.

Rice at ৳62.50 a kilogram

Each kilogram adds the same 62.50, so three kilograms cost ৳187.50.

Change from a ৳100 note

The bill is ৳68. Balance the sides and the change is ৳32.

A bus fare with a starting charge

The fare starts at ৳10 before you move, then adds ৳5 for each kilometre.

Ten per cent off the bill

10 per cent of ৳800 is ৳80, so the shopper pays ৳720.

Check what you know

Three questions on comparing decimals, a bill total and change from a note.

Shape, perimeter and area

Perimeter as the distance around the edge, a rule for the fence around a square, area as rows of square metres, taking one area away from another, estimating a curved area by counting squares, reflecting a shape, and the distance around a circle.

0/9

Perimeter is the distance around the edge

Drag a corner and the side lengths change. Add all four sides for the perimeter.

Preview6m 2.

A rule for the fence around a square

All four sides of a square are equal, so the perimeter is 4 times one side.

Preview5m

A longer field needs two more metres

Each extra square adds 2 m of fence, so the perimeters go 4, 6, 8, 10.

Area is rows of square metres

Each row of the field covers 8 square metres, so 5 rows cover 40.

The path around the pond

Find the outer area, then take the pond away. 140 minus 96 leaves 44 square metres.

Estimating a curved area by counting squares

Count the full squares, then count each part square as a half.

Flipping a shape over a line

A reflection keeps every length the same and swaps the sides of the mirror line.

Around a circle: a little more than three times across

Roll a wheel once and the distance is always about 3.14 diameters.

Check what you know

Three questions on perimeter, area of a rectangle and estimating an area.

About the creator

8bitlesson

Cambridge O Level, A Level and university courses, taught through interactive labs.

Mentora builds the sciences and mathematics as things you can move rather than videos you watch. Cambridge O Level and A Level mathematics, physics, chemistry and accounting, a primary mathematics track, and first-year university computer science. Every lesson works a real exam question end to end.