BERKLEY, Mich. (AP) _ A high school honor student and gymnast in this Detroit suburb has been charged with armed robbery and is a suspect in several others, allegedly to support a $200-a-day heroin habit.

Sarah Plumb, 16, is in a juvenile lockup, awaiting trial as an adult on charges that could land her a life prison sentence.

In all of the stickups, the robber said she had a weapon but did not show it, police said. Michigan law requires only the threat of a weapon for an armed-robbery conviction.

Defense attorney Howard Arnkoff said Ms. Plumb should have been handled as a juvenile and should have been charged with something less than armed robbery, since no weapon was displayed.

``If she gets convicted, its a non-probational offense. She must be incarcerated. She must be sent to prison. And I seriously doubt she could get the help she needs,'' he said.

News of her arrest shocked the low-crime community of 16,000 that typically only has a half dozen stickups each year.

``This is very scary,'' said Berkley High School spokeswoman and media instructor Gwen Ahearn. ``The kids were surprised about the heroin.''

``Typically, hard drugs are few and far between,'' Detective Sgt. Ray Anger said Wednesday. ``Possibly a couple other kids are users of serious drugs, but I don't know.''

Though she denies committing the robberies, Ms. Plumb admits she is a heroin addict. She was arrested Dec. 21.

She told police she began using the drug at 14 when a co-worker at a pizza parlor introduced her and her boyfriend to heroin.

Last June, she got caught cashing a forged check stolen from the high school and confessed she was using the money to buy heroin, Anger said.

The robberies began last month, police said.

About 6 p.m. on Dec. 2, wearing a skull Halloween face mask, she allegedly entered an Amoco station next to the high school and told the 17-year-old clerk _ a fellow student _ that she had a weapon.

Ms. Plumb made off with $300, then went to her gymnastics team practice, police say.

She later tried to rob a BP station in Royal Oak on Dec. 14, then robbed a beer and wine store in Berkley the same day, a pizzeria in Clawson on Dec. 15 and another pizzeria in Southfield on Dec. 16, Anger said. She has not been charged in those holdups.

A friend tipped police to Ms. Plumb as a suspect in the first robbery.

The arrest created such a buzz among Berkley High School's 1,300 students Wednesday that the administration took to the PA system to discourage rumor-mongering about it.