Rosh Hodesh and Jewish Calendar Overview


The Jewish calendar is traditionally a central component of Jewish experiences. This unit brings that calendar to life by exploring how the calendar is calculated and how it connects individuals to a larger Jewish community. Students are introduced to a different era of Jewish history through classical text study while having the opportunity to apply their lessons to real life through ongoing introspection and engaging activity. Simultaneously, this unit sets the stage for a yearlong emphasis on holidays as islands of time when Jewish people celebrate together as one.

Learning Experiences:

Student learning begins with a realization that the Jewish community shares a connection to a unique calendar and that this calendar provides its own set of birthday celebrations. Students observe the moon in order to understand its role in shaping the Jewish calendar and apply their knowledge in the creation of a class calendar that incorporates moon phases, Jewish dates, Jewish holidays, and Jewish birthdays. They participate in an interactive treasure hunt that reviews the Jewish months of the year and sing a song to help them remember the names of the months. Through text study and a reenactment of the Sanhedrin, students realize the emphasis placed on the calendar at the time of the Mishnah; through introspection and the creation of their own Birkat Hahodesh prayer, students realize the role that the calendar can play in their own lives.

Core Concepts:

The Jewish calendar enables all Jews to celebrate holidays at the right time, as one people.

Enduring Understandings:

  • The Jewish people has its own calendar that is linked to the Torah.
  • The Jewish calendar is different from the civil calendar in that it is tied to the phases of the moon and to the seasons.
  • During the time of the Mishnah, the Sanhedrin was very careful to make sure that everyone celebrated Rosh Hodesh at the right time.
  • Rosh Hodesh is a time for celebration and blessing.

Essential Questions:

  • Why do we have a separate Jewish calendar?
  • How is the Jewish year organized?
  • How might I mark a new Jewish month in traditional and/or personally meaningful ways?

Unit Framework and Core Concepts

Lesson 1: Experiencing Two Birthdays

Students will learn that they have Jewish birthdays in addition to their civil birthdays; they will understand that there is an instruction in the Torah to create a Jewish calendar.

Lesson 2: The Jewish Calendar and the Moon

Students will study the phases of the moon to help them understand how the Jewish calendar is set; they will use observations of the moon and/or a lunar phase calendar to create a Jewish calendar for an upcoming month.

Lesson 3: The Jewish Months

Students will learn the names of the Jewish months and will create a visual representation that helps them associate each month with major holidays that fall within it.

Lesson 4: Mishnah Rosh Hashanah

Students will work with a havrutah to study the Mishnah that describes how the new month was decided and announced in the time of the Temple. They will reenact the content of the texts as a class.

Lesson 5: Birkat Hahodesh

Students will learn to read or sing the Birkat Hahodesh and will create a page for their personal siddurim that includes their own wishes for the upcoming month.

Lesson 6: Ongoing Project: It's Rosh Hodesh!

Students will work in small groups to make plans to announce one Rosh Hodesh to the rest of the school in a way that reflects what they have learned from the Mishnah. Each month:
  • all students will write their hopes for the new month, and one group will announce the new month to the other classes in the school; and
  • one group of students will execute the plans they created to announce the new month to the school.

Additional Considerations:

The beginning of Lesson 4 must be taught BEFORE Rosh Hodesh because the second half of the lesson includes a new-moon observation that begins at home and requires follow-up AFTER a Rosh Hodesh has passed. Therefore, the sequence of the unit may require some adaptation, depending on how the timing of Lesson 4 falls in relation to Rosh Hodesh. Before beginning the unit, look at a Jewish calendar to see how this Lesson 4 will likely fall in relation to Rosh Hodesh. If it will fall immediately after Rosh Hodesh, consider teaching Lesson 4 prior to Lesson 3 to accommodate the new-moon observation. If it will fall a couple of weeks before Rosh Hodesh, consider teaching Lesson 4 until the new-moon observation is assigned. Stop in the middle of the lesson. Teach Lesson 5 or Lessons 5 and 6 or Lessons 5, 6, and the beginning of the next unit, depending on what is necessary to work within the calendar. Then return to Lesson 4.

Learning Objectives and Performance Outcomes

Learning Objectives

Performance Outcomes

Students will demonstrate knowledge that:

The Jewish calendar is important because it enables all Jews to celebrate holidays simultaneously, as one community.

Students will reflect upon the reasons that the Torah highlights the need for a Jewish calendar.

The Jewish calendar and the timing of the Jewish holidays are based on the moon.

Students will appropriately place lunar phases and Jewish holidays onto the Jewish calendar.

The Mishnah describes a complicated process through which witnesses were questioned about the new moon.

Students will reenact the process of questioning witnesses and testifying about the sighting of the new moon.

On Rosh Hodesh, we ask God to give us a month of blessings.

Students will create wishes to say with the Birkat HaHodesh

Students will express feelings of:

Connection to the Jewish people

Students will discuss the Mishnah's emphasis on ensuring that all Jewish people celebrate Rosh Hodesh at the same time.

Students will be able to:


Describe the lunar cycle and its relationship to the Jewish calendar.


List the Jewish months in order and identify the holidays that fall within them.

  Recite the first line of Birkat HaHodesh

Assessment and Rubrics

Student work will be assessed according to the following criteria:

To what extent

  1. Do reflections demonstrate thought about the importance of the calendar?
  2. Do prayers and monthly journals demonstrate a sense of introspection?
  3. Do students create a plan to announce Rosh Hodesh that reflects what they have learned in class about the connection between the moon phases and Rosh Hodesh and/or the way Rosh Hodesh was declared and announced at the time of the Mishnah?
  4. Do students participate and work well with havrutot and small groups?
  5. Do students participate in the moot Sanhedrin in a way that demonstrates understanding of the Mishnah?
  6. Do students explain their ideas clearly so that they are easily understood by others? Is their writing clear?
  7. Is students’ work well organized? Are their names on all parts of their projects?
  8. Do projects show effort? Are worksheets completed thoroughly? Does it look as though students spent a good amount of time working on projects, or do the projects look as though they were done very quickly?