Timelines are a valuable teaching tool especially in subjects such as history and science. Plotting events on a visual line in chronological order helps students understand and remember the significance of important dates. Students also gain a sense of how history connects the present with the past. Before you teach timelines to third graders, however, you need to explain the concept of time periods, and how large sections of time are divided.

### Step 1

Explain the numerical concepts relating to the time periods your class is studying. At the third-grade level, most students have no idea there's a difference between an era and an epoch, and many don't yet fully understand the ideas of decades, centuries and millenniums. If your lesson includes the history of the fossil record, explain the difference between "era," "epoch," "period," and "age." If you're studying a chunk of human history, explain the difference between "year," "decade," "century" and "millennium."

### Step 2

Explain the concept of a "timeline," and how each point on the line represents a date in history. If students have trouble with the concept of time being represented linearly, make a simple example along the lines of, "In real life we can only move forward into the future, not backward into the past, and the left to right increase in the dates on the timeline represent time moving forward from the past to now."

### Step 3

Select a period of time for the students to plot on a timeline, and give the students a specific number of events from that period. If the class is history, you could look at a century in detail, or perhaps even look at an entire millennium. If the class is about the history of life, you could look at an entire era or epoch. Explain how each date corresponds to an event: for example, 1776 for the signing of the Declaration of Independence, or 27 B.C. for the creation of the Roman Empire.

### Step 4

Demonstrate how students can use a ruler to create a scale for accurately spacing historical dates on a line. Convert the years of the period into more manageable chunks of time, such as 10- to 50-year blocks. For example, if your lesson focuses on the period from 0 to 2000 A.D. and you want to plot the birth of Jesus, the deposition of Romulus Augustus, the fall of Constantinople and America's declaration of independence, you could draw a 12-inch line with a ruler, and divide that line into 20 100-year segments. Label Jesus at 0, Romulus between 400 and 500, the fall of Constantinople between 1400 and 1500 and America's independence between 1700 and 1800.

### Step 5

Provide students with rulers and markers and give them an opportunity to make their own timeline based on the method taught above. This can be done by students alone or in groups. Assign a time period or let their students choose their own dates to put on the timeline. Constructing their own timelines will help the students to recognize the lengths of time represented on timelines they encounter in the future.