Hi Padma,
Even i have been hearing about Abacus a lot.....From what I know, it helps the child do mental mathematics and large calculations fast.....I asked a lot of moms before enrolling my son in the abacus class.....everyone said it had helped their child in mathematics. my son completed three levels and then left.....it was not too difficult and he did pretty well.....and i am thinking of putting him in the classes again.(the good part about these classes is that one can leave at a pt and still continue after a gap)
my son still uses the traditional method for calculations as he finds it easier but i think for bigger nos. abacus will definitely be handy.
the only thing to keep in mind is that the child sh. practice it regularly so that it becomes a habit for him/her otherwise it is a bit difficult to switch to this method of calc. once they r used to the traditional way.
then there is vedic mathematics also which i assume is also more or less the same but ancient indian . if somebody knows more about this , pl. share ur views here.
regards
sonalika