Here are some Internet sources for exploring the contrasting readings of the history and significance of the Indus Valley Civilization. Go ahead and do your own research, try http://www.google.com/and search for more!!

If you ever thought the IVC was dead and gone.... well think again!! Below I present just SOME of the many controversies around the IVC which appear on the WWW.
 

1. But let me start by presenting not "raging" controversies, but different "official" histories. Below are the OFFICIAL sites of two governments. Contrast the representations of IVC in the official web-pages of the Governments of India and Pakistan. Do you see a difference? Can you read the subtle and not-so-subtle differences in emphasis and orientation, even when so many "facts" remain the same! 

http://www.heritage.gov.pk/indus-1.1.html

http://www.indiagov.org/culture/history/history.htm
 

2. One set of people who have really taken up the IVC as their "cause" have been Hindu nationalists from India, whose agenda is to emphasize the HINDU heritage of India, and define religious groups like Muslims and Christians as "foreigners." From the links below, can you figure out why a reinterpretation of the IVC and denying the foreign origin of the "Aryans" or the Vedic people is so important to them? For some background on Hindu nationalism or Hindutva, follow links from http://www.sas.upenn.edu/~dludden/rss-history.htm
 

 Hindutva and History by Romila Thapar
 

 Horseplay in Harappa

Saffron Touch to Aryan-Harappan Link

NOTE: Some of the stuff below will make more sense if you read ahead just a little bit to the Vedic age. 

http://www.hindunet.org/hindu_history/ancient/indus/indus_civ.html

http://www.hindunet.org/hindu_history/ancient/aryan/aryan_frawley.html (a "scholarly" account)

http://www.hindunet.org/hindu_history/ancient/aryan/aryan_link.html (links to different Hindu nationalist readings of history) 

http://hindunet.org/hindu_history/sarasvati/

3. But then information or propaganda on the "net" is seldom left uncontested. To see a "Muslim" response to the Hindu nationalist readings of the IVC, see: 

http://muslimsites.com/mughalstan/hindutva/aryan.html
 

Alternatively, more Pakistan-centric readings of the IVC can be found at: 

http://www.pakcenter.com/reading/information/culture/Culture/IndusValley.html

Two interesting Pakistani newspaper article on the subject can be found at:

http://www.paknews.org/articles/nov98/art2nov-01.html

http://www.paknews.org/articles/dec98/art1dec-21.html

A less polemical article, demonstrating the impact of IVC on Present day Pakistan athttp://asnic.utexas.edu/asnic/subject/peoplesandlanguages.html

4. If you thought the Hindu-Muslim or India-Pakistan angle was there was to historical controversies, well, think yet again! The notion that "Dravidians" were the original inhabitants of India who were pushed out by invading "Aryans," also has an important presence in debates about Indian history. Present-day Dravidian nationalism claims much of southern India as its political constituency, and is certainly an important ideology in the southern Indian state of Tamilnadu. Why do you think proving the IVC to be a "Dravidian" civilization is so important? Why is it important for others, particularly Hindu nationalists, to contest such interpretations? Read below and see if you can figure it out!

http://www.geocities.com/Athens/Parthenon/2104/indusvalley.html

http://forumhub.com/tnhistory/8786.25990.17.50.20.html

AND
http://www.balilife.com/spirituality/dharmacollection/worldspirituality/aitagrawal.htm

(A Hindu nationalist refutation of the Dravidianist interpretation) 

.... And you thought you'd be reading only ANCIENT history :-)