Ask any parent of a teenager — or anyone who remembers those awkward years — and they will tell you that adolescence can be an extremely challenging period.

But it doesn't have to be that way, says Laurence Steinberg, a Temple psychology professor and leading international scholar on teen behavior and brain development.

In his newly revised book, You and Your Adolescent: The Essential Guide for Ages 10-25 (Simon & Schuster, January 2011), Steinberg offers parents practical tips for navigating the tricky terrain of the teen years. As an expert in the area of teen decision making and impulse control, his advice to parents is informed by the most current scientific findings.

"Adolescence has changed dramatically since today's parents experienced it, and so has our understanding of it," Steinberg said.

For one thing, adolescence now lasts longer. Once limited to the years from 13 to 18, adolescence as a psychological stage now begins at 10 and extends through the mid-twenties.

As a result, says Steinberg, parents find themselves faced with typical teen issues, such as having their parental authority tested, much earlier than they expected. And parents must deal with issues like financial support and conflicts over household chores much longer than they ever imagined.

"These days I get almost as many questions from parents about dealing with 20-somethings as I do about teenagers," he said.

Also new to this stage of life is the presence of electronic media and technology. As a consequence, today's parents have to understand how to monitor their kids' use of the internet and how to respond to incidents of cyberbullying.

Fortunately, new research on the adolescent brain can tell us a lot about teenage behavior, said Steinberg. Scientists now know that adolescence is a time of tremendous brain development.

"Failure to understand changes in the way young adolescents think is a leading cause of conflict between parents and teenagers," said Steinberg.

According to Steinberg, the teenage brain is a lot like a car with a powerful gas pedal and weak brakes. "While the gas pedal responsible for things like emotional arousal and susceptibility to peer pressure is fully developed, the brakes that permit long-term thinking and resistance to peer pressure need work," he said. "Parents will have to remind teens regularly to use their brakes."

Steinberg's work on teen behavior has played critical roles in several Supreme Court rulings that have changed the direction of juvenile justice — one ruling abolished the death penalty for juveniles and the other outlawed life-without-parole sentences in non-homicide cases for those under 18.

"As a scientist, I have always been interested in the translation of research for real life application," said Steinberg. "My research is grounded in practical considerations. And my book is grounded in science."

While most books in the adolescent section of the bookstore are either problem-oriented —  focused on taking a close look at a particular issue such as substance abuse or eating disorders — or are written as "survival guides," Steinberg compares his book to an "owner's manual."

"I think adolescence is a great time," said Steinberg. "Knowledge is what today's parents need."