The Federal Communications Commission and cable and computer firms will announce Wednesday a program to provide low-income homes with $10 monthly broadband Internet service and $150 computers.

The plan aims to solve one of the more vexing problems in the government’s quest to connect all Americans to the Internet: Even when people have the ability to subscribe to high-speed service, 100 million households don’t choose to do so.

Experts say that’s largely because of cost. The price of high-speed Internet averages $40 a month, and computers can cost several hundred dollars.

But beginning in the spring, cable Internet service providers such as Bright House, Comcast, Cox and Time Warner will offer families that are eligible for federal school-lunch programs — 25 million Americans — the discounted monthly service. The service will include free installation and modem rental for two years.

Redemtech, a computer refurbishing firm, will offer those families laptops or desktops for $150, with free home shipping and 90 days of tech support. Microsoft will provide new computers for eligible school-lunch families for $250.

The plan is part of the FCC’s drive to get all Americans onto high-speed Internet networks. FCC Chairman Julius Genachowski has warned that other countries are surpassing the United States in broadband Internet adoption — a trend that could hurt the economy in the long run.

“The cost of not adopting broadband, the cost of exclusion is high and getting higher,” Genachowski said in a telephone interview Tuesday.

Americans who aren’t connected, however, cite several reasons for not signing up for broadband. They say they need more training on computers and on the Internet, and some say the Internet isn’t important to their lives, according to the Pew Research Center’s Internet and American Life Project.

Some experts say those who aren’t using the Internet are missing out on key economic and social opportunities. Many employers and universities, for example, require candidates to apply online.

“We are proud to support this coordinated, community-based partnership to help educate, empower and enlighten new digital citizens so that they, too, will benefit from the Internet’s transformative potential,” said Michael Powell, president of the National Cable and Telecommunications Association, the cable industry’s major trade group.

Cable Internet service companies will provide 1 megabit-per-second speeds to eligible families that aren’t already subscribers and have clean accounts. The program won’t apply to families with overdue bills or unreturned equipment.