Saturday 8 September 2007

Magical 7 pieces

Tangram is a chinese puzzle, which has added a creative enhancement dimension to the learning of mathematics.

Mathematics is taught in the classroom ,having more focussed approach on textbook and the syllabus. A classroom learning scenario can be changed by adding more value to the learning of the subject through creative involvement of mathematics other than the textbooks. One such technique is using tangrams for teaching various mathematics concepts. I have explored tangrams and its utility in mathematics taeching.
Here I am sharing, how tangrams can be added to a classroom for teaching concepts like area of geometrical figures viz. square, right triangle, parallelogram etc.
I asked my students to make tangram pieces on a graph paper from the instructions given on the following link

The students then calculated the area of each cut out shape by counting the complete squares and half squares method.

This way they learnt various properties of geometrical figures.

By paper folding tangram can be easily made. The instructions are explained on the following link

Tuesday 4 September 2007

Salute to my teachers

Tommorow is Teachers day 5th September.

India has been celebrating Teacher's Day on 5th of September since 1962. 5th of September is the birthday of Dr Sarvepalli Radhakhrishnan, a philosopher and a teacher par excellence. Some of his students and friends approached him and requested him to allow them to celebrate his birthday. In reply, Dr, Radhakrishnan said, "instead of celebrating my birthday separately, it would be my proud privilege if September 5th is observed as Teacher's day". The request showed Dr.Radhakrishnan's love for the teaching profession. All this lead to Teachers Day origin in India.
On the occasion of Teachers day I would like to express my gratitude to all my teachers from Kinder Garten to the Professional college for shaping my life and showing me the right path by providing their valuable guidance. I think, a teacher is like a candle which burns to spread light everywhere.

The mediocre teacher tells. The good teacher explains. The superior teacher demonstrates. The great teacher inspires. --William Arthur Ward

Exploring GeoGebra

Potential of GeoGebra is extraordinary!
I am using GeoGebra for teaching geometry to my students. In class IX, C.B.S.E. Syllabus the properties of circles are taught. I have realised that the students cram the theorems without actually understanding their meaning. At the time of examination they do not attempt the questions based on application of geometry. This year I tried this open source software for teaching the properties of circles . Due to the interactive interface of the software, the students can visualise the geometrical theorems by actually verifying them using the tools available.
For example , the theorem "angle subtended by an arc at the centre of a circle is twice the angle subtended by the same arc at any other point on the remaining part of the circle"
The students do the theoretical proof of this theorem and simply cram it.
I tried learning this theorem using GeoGebra with the students, and the outcome was incredible.


The software is very easy to use by the teacher as well as the students. It is freely available and can be easily downloadable.

The verification of other properties of circles can also be done in the same manner.

Monday 3 September 2007

Sutra 1

This means "By one more than the previous one"
I am sharing one example where this sutra is applied.
Finding the square of a number ending with 5.
= [6 X (6+1)] 25 = 4225
For this number , the last digit is 5 and the 'previous' digit is 6. Hence, 'one more than the previous one', that is, 6+1=7.
The Sutra, in this context, gives the procedure 'to multiply the previous digit 6 by one more than itself, that is, by 7'. It becomes the L.H.S of the result, that is, 6 X 7 = 42. The R.H.S of the result 25.

= [8 X (8+1)] 25 = 7225
For this number , the last digit is 5 and the 'previous' digit is 8. Hence, 'one more than the previous one', that is, 8+1=9. The Sutra, in this context, gives the procedure 'to multiply the previous digit 8 by one more than itself, that is, by 9'. It becomes the L.H.S of the result, that is, 8 X 9 = 72. The R.H.S of the result 25.

Saturday 1 September 2007

Vedic Mathematics

Vedic Mathematics is the ancient system of Mathematics which was rediscovered from the Vedas between 1911 and 1918 by Sri Bharati Krisna Tirthaji (1884-1960). According to his research all of mathematics is based on sixteen Sutras or word-formulae.