A Lunar Dance with the PJ Library Perpetual Jewish Calendar

By Danny Paller
Content and Family Experience Officer, PJ Library


Even though it’s central to Jewish life, the Jewish calendar can be perplexing for grownups and kids alike. The PJ Library content team set out to demystify the yearly Jewish cycle with a brand-new tool for families.

Perpetual Calendar

The Jewish calendar is unique: Days begin at night. A new moon signals a new month. An entire month is added in a leap year. And then there are the holidays — lots and lots of them, some lasting a day, others a week. There’s even a holiday — Shabbat — that comes every single week.

PJ Library has always placed great emphasis on Jewish holidays. Each year all children receive books about Hanukkah and Passover, and many receive books about other holidays. In-the-envelope pieces are often holiday themed, like a DIY Purim gift basket or a Tu B’Shevat microgreens growing kit. In recent years, the new PJ Library Passover Haggadah has been widely distributed, and a fall holiday guide will be released in fall 2022.

But the Jewish calendar itself remains a mystery to many.

The PJ Library content team decided to do something about that. We wanted to help families understand how the Jewish calendar works by providing a fun, clear tool for marking Jewish holidays and events. And we wanted to give children an opportunity to experience what’s unique about the Jewish calendar and give curious parents more nuanced information (for example, why do Jewish holidays come "early" or "late"? Why do some Jews observe one day of a holiday and others observe two?).

That led to the birth of the PJ Library Perpetual Jewish Calendar, which was sent in August 2021 to all PJ Library families in the US, Canada, the UK, Australia, New Zealand, and South Africa. The mailing included a blank calendar, reusable sticker sheets of months and holidays, and an instruction sheet.

Though this seems like a simple enough concept, representing the Jewish calendar visually is no easy task. Here are some of the challenges we faced in creating this perpetual calendar.

Challenge #1: Sunset, Sunrise

A Jewish day begins at sunset, as inspired by the creation story in Genesis: “And there was evening, and there was morning, the first day” (Genesis 1:5).

But how would the PJ Library calendar show that all days of the Jewish year — and, most significantly, all Jewish holidays and Shabbat — begin at sunset and continue until after sundown the next day?

We decided to let the shape of the stickers do the talking. Each holiday and Shabbat sticker is shaped to begin at sunset on one day and end after sunset the next day.

Each time children place a sticker on the PJ Library calendar, they’re reminded of a key secret of the Jewish calendar: Days start at night!

Challenge #2: Moon Children

A powerful way to experience the Jewish calendar is to go outside and find the moon. On Rosh Hashanah, before we dip our apples in honey, the moon is new and eager to grow — just like we are as we begin a new year. On Passover, before we take our first bite of crunchy matzah, the moon is full and looks gloriously liberated — just like us on the Festival of Freedom. In fact, on any (nonovercast) night of the year, we can look up and know what part of a Jewish month — beginning, middle, or end — we’re in. We can appreciate how each Jewish month begins with a new moon and celebrates the possibility of renewal.

But how can this calendar help connect families to the lunar dance that’s so basic to Jewish life?

First, for holidays that are accompanied by a new moon (Rosh Hashanah and the sixth night of Hanukkah) or a full moon (Sukkot, Tu B’Shevat, Purim, and Passover), we embedded the moon in that holiday’s sticker — an invitation for kids to do some moon gazing!

Then we provided special stickers for the new moon (the monthly celebration called Rosh Chodesh) so families can mark the arrival of a new Jewish month and begin to follow the moon’s inspiring cycle.

Challenge #3: How Long Is “Perpetual”?

Our hope is that families will use this calendar throughout their kids’ childhood years to help them look forward to and prepare for Jewish holidays and remind them that Shabbat is never too far away. It encourages families to integrate both Jewish and other special events into their day-to-day lives.

By providing families with a reusable dry-erase calendar and stickers, our goal is to make this gift as long-lasting as possible. Besides the bonus stickers we provide for birthdays, playdates, seasons, vacations, schooltime, and more, there are also blank stickers so families can create whatever will make their PJ Library calendar fun and relevant.

Most importantly, we also created a digital calendar. Just as the moon has its sun, the PJ Library perpetual calendar has pjlibrary.org/calendar. Here families can scroll through a digital version of the calendar to see where holidays fall in the coming years. They can see when the new moon comes each month — in fact, there’s a picture of the moon for each night of the year. And there’s a listing of Jewish holidays for each year in perpetuity — now we’re talking! — and even a function to convert a Gregorian date (for example, a child’s birth date) into a Jewish one.

The webpage that features the digital calendar also offers videos and blog posts that answer commonly asked questions about the history and architecture of the Jewish calendar and what connects different Jewish holidays.

PJ Library is about supporting families’ Jewish journeys, and we hope the PJ Library Perpetual Jewish Calendar will support families as they take their own personal journeys through Jewish time.