RICHMOND -- Virginia will begin getting tougher on sex offenders, owners of dangerous dogs and underage drinkers on Saturday, when laws passed during the 2006 General Assembly session take effect.

The new criminal penalties are among the more noteworthy changes to state laws taking place Saturday, when the state also begins a new fiscal year. Virginians will see some minor tax changes implemented over the next year, including a three-day sales tax exemption on school-related purchases during the first weekend of August.

The state government came perilously close to beginning the fiscal year without a budget because of a protracted standoff between the Senate and House of Delegates over tax policy and spending priorities. Lawmakers passed a $72 billion spending plan last week, keeping state government running and covering costs associated with enacting new laws.

Few of the state's new laws have received as much attention as those aimed at increasing penalties and improving monitoring for sex offenders who target children. Attorney General Bob McDonnell made an aggressive push for the legislative package, which received broad bipartisan support from lawmakers and Gov. Tim Kaine.

"Those who harm innocent children have no place in our society, and this legislation makes every child in Virginia safer," McDonnell said after Kaine signed the legislation in April.

The state will impose a mandatory minimum sentence of 25 years for a first offense of rape, forcible sodomy or object sexual penetration of a child younger than 13 that occurs with an abduction, burglary or serious bodily injury. The law also requires some registered sex offenders to wear electronic tracking devices after their release from prison.

The tougher penalties are accompanied by upgrades and new reporting requirements for the state's sex offender registry and the expansion of a civil commitment program that keeps certain sex offenders confined for treatment after their prison terms expire.

"These new tools will help our police and prosecutors track, treat and punish those who pose a threat to our children and others in our communities," Kaine said when he signed the legislation.

The state also will get tough with owners of dangerous dogs. Under a new law, a dog will be declared dangerous if it attacks and injures a person or attacks a dog or a cat outside the owner's property. Once a dog is deemed dangerous, the owner could face a felony charge that carries a maximum penalty of five years in prison if the dog seriously injures another person. Lawmakers passed the measure in response to last year's mauling deaths of a Spotsylvania County woman and her small dog by roaming pit bulls.

Lawmakers also approved new measures to punish underage drinkers and their enablers. Virginians younger than 21 who are convicted of purchasing or possessing alcohol will face mandatory suspension of their driver's license for at least six months. Anyone older than 21 who provides alcohol to someone younger than 21 also could have their license suspended. The law does not prohibit serving alcohol to family members at home or to guests who are accompanied by a parent, guardian or spouse older than 21.

Virginia's first sales tax "holiday" for back-to-school shoppers will occur Aug. 4 - 6. On those three days, shoppers won't pay the state's 5 percent sales tax on school supplies priced at $20 or less or on clothing and footwear priced at $100 or less. State officials expect the modest tax break to save shoppers $3.6 million.