Study by network

When college students want to contact a friend or see pictures from last weekend's party, most head for a social networking site like Facebook-but students have not flocked to websites that help them share notes or study together. For example, Inigral's "Courses" application for Facebook flopped in 2008, possibly because potential users were less than enthusiastic about doing homework and browsing pictures on the same website.

Developers are betting that today's users will be more receptive to the idea. Companies have been busily creating software to let students share notes, sample essays, and access other resources with classmates. One such site is Grade Guru, developed by textbook publisher McGraw-Hill Education. Users can upload notes for classes, and the site offers rewards such as cash or gift cards for those with the most popular notes. Developers at Purdue University created an application for Facebook called Mixable that allows students to share notes and other documents with their friends.

Though such sites have the potential to be useful to students, some professors raise questions about the ethics and educational usefulness of sharing notes through social networking: Will students pay less attention in classes? Companies are still figuring out how to keep entire exams with answers and similar materials off the sites.

Data trove

Nearly a year and a half ago, the White House began putting raw government data sets online, making information about topics from public health to ozone readings to foreign aid available to the public. But there's an enormous amount of data-270,000 data sets to date-and the sheer quantity makes it difficult to sift through. The U.S. chief information officer, Vivek Kundra, has said that "data curation" will become a burgeoning industry in the near future.

One group of computer scientists and students at Rensselaer Polytechnic Institute in Troy, N.Y., is creating tools to help ordinary people turn all of these numbers into information they can understand. The tools are not ready for public use-programmers hope they'll be available in a year or two-but some demos are available on the web (data-gov.tw.rpi.edu/wiki/Demos). One demo lays data about library books per capita onto a map of the United States to show the "density" of books in each state; another links Medicare claims in states to interstate travel. Visitors to the site can see information about campaign money in each state, interstate migration, justices of the Supreme Court, and much more.

Twitter profile

Research analysts are increasingly turning to Twitter to study the "buzz" around political or cultural events and topics-but a Pew Research Foundation study reports that only 8 percent of active internet users in the United States use Twitter on a regular basis. Twitter users are mostly minorities, young adults, and city-dwellers: African-Americans and Latinos are twice as likely to use the service as whites, and people in cities are twice as likely to Tweet as those in rural areas. The researchers also noted that Twitter is nonetheless one of the most popular services among internet users.