[CBSE]Maths Course Structure - Class VIII

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Number System (50 hrs)


(i) Rational Numbers:



Properties of rational numbers.(including identities). Usinggeneral form of expression to describe properties



Consolidation of operations on rational numbers.



Representation of rational numbers on the number line



Between any two rational numbers there lies another
rational number (Making children see that if we take two rational
numbers then unlike for whole numbers, in this case you can keep
finding more and more numbers that lie between them.)



Word problem (higher logic, two operations, including ideas like area)


(ii) Powers



Integers as exponents.



Laws of exponents with integral powers


(iii) Squares, Square roots, Cubes, Cube roots.



Square and Square roots



Square roots using factor method and division method for
numbers containing (a) no more than total 4 digits and (b) no more
than 2 decimal places



Cubes and cubes roots (only factor method for numbers containing at most 3 digits)



Estimating square roots and cube roots. Learning the process of moving nearer to the required number.


(iv) Playing with numbers



Writing and understanding a 2 and 3 digit number in generalized form (100a + 10b + c , where a,
b, c can be only digit 0-9) and engaging with various puzzles concerning this. (Like finding the
missing numerals represented by alphabets in sums involving any of the four operations.) Children
to solve and create problems and puzzles.



Number puzzles and games



Deducing the divisibility test rules of 2, 3, 5, 9, 10 for a two or three-digit number expressed in the general form.


Algebra (20 hrs)


(i) Algebraic Expressions



Multiplication and division of algebraic exp.(Coefficient should be integers)



Some common errors (e.g. 2 + x ≠ 2x, 7x + y ≠ 7xy )



Identities (a ± b)2 = a2 ± 2ab + b2, a2 – b2 = (a – b) (a + b) Factorisation (simple cases only) as examples the following types a(x + y), (x ± y)2, a2 – b2, (x + a).(x + b)



Solving linear equations in one variable in contextual
problems involving multiplication and division (word problems) (avoid
complex coefficient in the equations)


Ratio and Proportion (25 hrs)



Slightly advanced problems involving applications on percentages, profit & loss, overhead expenses, Discount,tax.



Difference between simple and compound interest
(compounded yearly up to 3 years or half-yearly up to 3 steps only),
Arriving at the formula for compound interest through patterns and
using it for simple problems.



Direct variation – Simple and direct word problems



Inverse variation – Simple and direct word problems



Time & work problems– Simple and direct word problems


Geometry (40 hrs)


(i) Understanding shapes:



Properties of quadrilaterals – Sum of angles of a quadrilateral is equal to 360o (By verification)



Properties of parallelogram (By verification)




[list=disc][*]Opposite sides of a parallelogram are equal,[*]Opposite angles of a parallelogram are equal,[*]Diagonals of a parallelogram bisect each other. [Why (iv), (v) and (vi) follow from (ii)][*]Diagonals of a rectangle areequal and bisect each other.[*]Diagonals of a rhombus bisect each other at right angles.[*]Diagonals of a square are equal and bisect each other at right angles.[/list]


(ii) Representing 3-D in 2-D



Identify and Match pictures with objects [more complicated e.g. nested, joint 2-D and 3-D shapes (not more than 2)].



Drawing 2-D representation of 3-D objects (Continued and extended)



Counting vertices, edges & faces &
verifying Euler’s relation for 3-D figures with flat faces (cubes,
cuboids, tetrahedrons, prisms and pyramids)


(iii) Construction:



Construction of Quadrilaterals:



- Given four sides and one diagonal



- Three sides and two diagonals



- Three sides and two included angles



- Two adjacent sides and three angles


Mensuration (15 hrs)



Area of a trapezium and a polygon.



Concept of volume, measurement of volume using a basic unit, volume of a cube, cuboid and cylinder



Volume and capacity (measurement of capacity)



Surface area of a cube, cuboid, cylinder.


Data handling (15 hrs)



Reading bar-graphs, ungrouped data, arranging it into
groups, representation of grouped data through bar-graphs, constructing
and interpreting bar-graphs.



Simple Pie charts with reasonable data numbers



Consolidating and generalising the notion of chance in
events like tossing coins, dice etc. Relating it to chance in life
events. Visual representation of frequency outcomes of repeated throws
of the same kind of coins or dice. Throwing a large number of identical
dice/coins together and aggregating the result of the throws to get
large number of individual events.
Observing the aggregating numbers over a large number of
repeated events.
Comparing with the data for a coin. Observing strings of
throws, notion of randomness


Introduction to graphs (15 hrs)


PRELIMINARIES:



Axes (Same units), Cartesian Plane



Plotting points for different kind of situations
(perimeter vs length for squares, area as a function of side of a
square, plotting of multiples of different numbers, simple interest vs
number of years etc.)



Reading off from the graphs



- Reading of linear graphs



- Reading of distance vs time graph
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