What does a 70-something Jewish grandmother have in common with a high school freshman?

More than one might suspect, members of the Rosh Chodesh New Moon women's group at Congregation Rodef Sholom are discovering.

The group, which enlists members between the ages of 14 and 90, meets at the San Rafael synagogue once a month on Tuesdays to celebrate the arrival of Rosh Chodesh, or the new moon.

Gathering in a circle around a candlelit table, mothers, widows and teenage girls share everything from their fears and aspirations to their thoughts on God and feminism.

"We have two things in common. We're women and we're Jewish," said Rabbi Stacy Laveson. "We can learn so much from each other."

Laveson, Rodef Sholom's second woman rabbi, founded the group a year and a half ago in response to the demand for a forum where women could explore their Jewish identities.

The rabbi chose Rosh Chodesh as the theme because the monthly phenomenon has traditionally been a time of reflection for Jewish women. Rosh Chodesh, Laveson said, is Hebrew for "head of the month," known in the lunar calendar as the new moon.

According to Laveson, the holiday harks back to the creation of the Golden Calf. Women, she said, did not contribute to the making of the calf; they rested and reflected.

In recent years, synagogues have embraced Rosh Chodesh as a way to reach out to Jewish women on spiritual jour-neys."Modern Jewish women have reclaimed Rosh Chodesh as a time for us and for personal and spiritual exploration," said Laveson. "It's been a way for them to engage themselves Jewishly."

The concept of Rosh Chodesh has apparently struck a chord with members of Congregation Rodef Sholom, where the New Moon women's group has attracted approximately 75 members, a third of whom attend meetings regularly.

During the 1-1/2-hour meetings, women perform rituals and discuss the theme of the month, which is usually, but not always, tied to an approaching Jewish holidays.

Past themes have included matriarchs, darkness and light, and letting go.

Although singing and candlelighting are common rituals, the group has also explored non-traditional modes of expression, such as mask-making.

At a recent meeting, members brought mops, brooms and scouring pads to address the symbolic act of spring cleaning.

"For many of our older members, it's the first time in their lives that they have been able to intimately discuss their role as women in Judaism and discuss some of the myths they were brought up with," Laveson said.

She added, however, that age barriers often dissolve as women begin to share their thoughts and feelings.

The spirit of openness has made a profound impression on Sylvia Korn of San Rafael. Korn, who is in her 70s, joined the group with some friends after her husband had a heart attack two years ago.

"I think being able to sit and talk with a group of women can be very healing because when you discuss incidents or life-cycle events in your life you find that other people have similar experiences," Korn said. "It's a good feeling. It really helps."

Korn said she is always touched by the way the young and old share their lives with each other. "Age doesn't seem to have any interference at all."

Hannah Engle, 14, of San Rafael, had a similar experience when she tagged along with her mother and 16-year-old sister.

"It was really interesting," said Engle, who especially enjoyed learning about Jewish mysticism. "I like that it was all women and really open. It was something kind of new."

Engle said she went back a couple of times. At one session, she wrote a letter to herself, which she mailed later.

Though Engle still hasn't received the letter, she hasn't lost faith in the group. She is planning on going back just as soon as her homework and social life let up.