Thinking about sending a little money to a group that says it is helping the families of the astronauts killed in the space shuttle Columbia disaster? Some charity watchdog groups and state regulators are advising would-be donors to ask questions before pulling out their checkbooks or credit cards.

"There is public sympathy for a horrible tragedy. People want to help, and there are some people that seem to take advantage of that," said Bennett Weiner, a spokesman for the BBB Wise Giving Alliance, an Arlington-based charity watchdog group that issued a warning yesterday that the scam artists are back.

This time, Weiner said, they're trying to fleece donors by promising that donations and purchases of shuttle memorabilia will benefit the grieving families of the seven astronauts.

The shuttle broke up over Texas on Feb. 1, leaving behind six spouses, 12 children and other family members.

In the past week, several state agencies and other organizations have sought to rein in budding scams after reports of fraudulent telephone and online solicitations from organizations claiming to help the astronauts' families.

Texas Attorney General Gregg Abbott issued an alert last week about possible telephone and e-mail scams related to the shuttle disaster. And the Better Business Bureau serving parts of Washington state and Idaho issued a similar warning after tracking down a self-employed salesman in Spokane, Wash., who set up a Web site touting a "humanitarian organization" raising funds for the Columbia families.

The site has since been disabled.

As well, e-Bay, the online auction giant, is advising its customers to be wary of auctions on its site conducted by anyone claiming the funds will benefit the Columbia families.

For its part, NASA is pointing would-be donors to the Space Shuttle Children's Trust Fund, set up by District lawyer Delbert D. Smith in 1986 to pay educational expenses for children of the astronauts on the shuttle Challenger, which blew up during its launch in January that year.

A NASA spokesman said yesterday that that fund, which raised about $1 million, paid for the college educations of 11 children of the Challenger astronauts.

A spokesman for Smith, the trust fund's chairman, said that efforts seeking donations for the fund "have been reactivated because of the unfortunate tragedy" involving the Columbia. The address for donations is: Space Shuttle Children's Trust Fund, P.O. Box 34600, Washington, D.C. 20043-4600.

A Web site, www.spaceshuttlekidsfund.org, is expected to be operational today.