Beacon Lesson Plan Library

Age Is Relative

Lynda Penry


Students calculate how old they are in three units: months, weeks, and days. Then, they write about how they solved the problems.


The student solves real-world problems involving addition, subtraction, multiplication, and division of whole numbers using an appropriate method (for example, mental math, paper and pencil, concrete materials, calculator).


-Calculator for each two students
-Drawing paper for recording for each student
-Small calendar(s) for each of two students (I copy the calendar from my checkbook)
-Assessment Rubric (associated file)


1. Prepare small calendars for students’ use (ex.: copy calendar from checkbook)
2. Hand out drawing paper and calculators
3. Copies of rubric (or overhead copy).
4. Copies of assessment (or overhead copy of prompt).


1. Announce to the class a student’s age in months or days. (For example, a 9-year old student would be 108 to 119 months old.) Give them the numeric value, only, not the unit. Then ask them if that would be years, months, weeks, or days. Discuss what would be appropriate units.

2. Review how many days in one year, how many weeks in one year, approximately how many weeks in one month, and how many days in one month.

3. Have the students work with partners.

4. Explain to the students their tasks are to determine their age in months, weeks, and days. Have them refer to the calendar, if necessary.

5. The students are to record the answer for each unit and write and/or draw pictures describing how they found the answers.

6. Monitor students as they work to offer immediate feedback.

7. When completed, have students discuss the methods they used to solve the problems. Ask, “How did you find your age in months?” Request several responses because students use different strategies to solve the problem.

8. Check for understanding as you ask students various questions about the process of the assignment. Discuss reasonableness of the answers. (Ex.: Is it reasonable to think a student in the class could be 4,000 weeks old?)

9. Assessment: Students are to calculate their ages in minutes. Ask them to write their estimations first, then individually, write about how they would solve the problem, then solve it. You will need to model this for them and then circulate as they are working to make sure they are on the right track.


NOTE: This assessment may not address all four operations-addition, subtraction, multiplication, division. It depends on how the student solves the problem. A written assessment is included, asking students to solve a problem about time. The prompt is attached with a rubric to assess students' understanding. Conference with the students as soon as possible to offer feedback on this assessment. Using the rubric helps students to see specific strenghths and weaknesses.


Try graphing the results of the activity. As a class, determine the appropriate scale and which type of graph would display the data best.

Attached Files

An assessment prompt and rubric are included.     File Extension: pdf

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