Timelines: Benefits and Challenges
Creating Timelines to Teach the Concept of Historical Significance
As soon as a person begins making a timeline, they begin making choices about what to include — and choices about what to leave out. In other words, they make choices about what events or developments are historically significant. And the concept of historical significance is a really important aspect of historical thinking. It is at the root of understanding what the discipline of history is and how it is constructed. As Stephane Levesque argues:
Just think about this: Have you ever felt upset that you didn't learn about something in a history class? Have you ever heard someone else complain about what wasn't covered in their history classes? Or have students ever asked you why you didn't learn about a historical topic? The topic probably wasn't addressed because the historian or teacher had a different idea than their audience about what is historically significant. Or it wasn't addressed because the topic wasn't deemed historically significant at the time — after all, our ideas about historical significance change with time and place. According to Levesque, historians make choices about historical significance based on the following criteria:Because they cannot study everything that happened in the past, historians are necessarily selective in their own investigations. Certain historical events, personages, dates, or phenomena are more important to their studies than others...History, to be meaningful, depends on selection and this, in turn, depends on establishing criteria of significance to select the more relevant and to dismiss the less relevant.[6]
This is not necessarily how non-historians make choices about historical significance. As Levesque also argues, non-historians may make choices based on the following:
- Importance - Contextualizing the past and considering what was perceived as important to those who lived at the time, irrespective of whether their judgments about the importance of the event were subsequently shown to be justified.
- Profundity-How deeply people were affected by an event.
- Quantity-The number of people affected by an event.
- Durability-How long an event endures.
- Relevance-Relation to current interests, accepting the fact that we cannot divorce ourselves from being social actors in the present.[7]
And according to researchers Lauren McArthur Harris and Brian Girard, teachers make their own choices about instructional significance.[9] These include historical considerations, but also contextual and student considerations:Creating timelines offers students an opportunity to grapple with the concept of historical significance. In this activity, for example, students consider their own criteria for historical significance, compare it with historians' criteria, and then create a poster for "determining historical significance." Using an activity like this early in students' historical studies will prepare them for creating timelines for state, U.S. and world history, and it will help them analyze others' timelines knowing that they made choices about historical significance too.
- Intimate interests-Is this important to me personally? Do my loved ones have an intimate attachment?
- Symbolic significance-Selection of some events for patriotic or collective justification.
- Contemporary lessons-Use it to apply to the present. [8]
Analyzing Timelines for Continuity and Change or Cause and Consequence
So what about analyzing timelines? Is this an activity that can benefit students' learning? Interestingly, state standards documents do a pretty poor job of addressing analysis of timelines. In fact, only seven states explicitly require students to analyze timelines. In Michigan, for example, analysis of timelines is only mentioned in 2nd grade, where students are supposed to use timelines to distinguish between years and decades. Seventh grade is the last time timelines are mentioned at all. But timelines are everywhere in social studies texts. In a study of commonly used social studies textbooks, Shreiner found that timelines made up 14% of the nearly 3000 data visualizations contained in the textbooks. Even if state standards do not require students to analyze them, students are likely confronted with them on a regular basis.[10]
And there is much to be gained by providing students with guidance in reading and analyzing timelines. Analyzing timelines supports chronological reasoning about the past. In particular, it can help students identify continuity and change, as well as explore cause and consequence — two other historical concepts that are really critical for historical thinking. Continuity and change is about seeing history as more than a list of events, but as a series of related developments that either signal stability over time, or that show transformations or shifts over time. Recognition of such relationships is what has allowed historians to colligate, or group together, separate events into outwardly simple terms that actually denote complex or long-lasting processes — terms like "industrialization," "urbanization," or "revolution." Teachers can give students tools to analyze such relationships among events on timelines, helping them to recognize how and why events are related, what large-scale processes they might represent, or to what degree a sequence of events represents continuity or change.
Analyzing timelines can also provide students with insight into historical causes and consequences. Studies of students' thinking indicate that their explanations for why things happened are likely to be mono-causal — that is they tend to think one event led to another, which led to another, and so on, in what we might call a mono-causal chain. In some ways, uncritically viewing timelines — which are often represented as a simple line of events — can exacerbate such misconceptions. However, historians know that multiple causes and multiple consequences are almost always appropriate in explanations of the past. And causes can be grouped in any number of ways: political, social, or economic; proximal or distal; short-term or long-term; as playing the role of trigger or catalyst; or as more or less important. Timelines, such as the ones students find in their textbooks or interactive ones like the WWII timeline to the left, can serve as visual aids to help students both see a sequence of related events, and determine how the events are related in terms of cause and consequence. Students can annotate or categorize related events and then use their analysis to build arguments about an event or phenomenon of the past. Or they can build their own complex timelines that visually capture some of the nuances of cause and consequence in history, showing their causal categories using different symbols, colors, or timeline layers.
Unpacking Chronological Conventions and Temporal Concepts
But let's think further about the timelines students see in print and online texts. Are they easy to read? Even though they may seem pretty simple and straightforward, there are aspects that can be quite confusing, or even misleading. Consider the following timeline, which is from a popular world history textbook. Is there anything confusing about this timeline?Aside from the obvious editorial errors (10,000 what?), this timeline provides a glimpse of the many different chronological conventions — ways of indicating moments in time or the passage of time — that students have to interpret. Readers see "years ago" on one end of the timeline, and the years themselves on the other end. They also see the notation "ca.," the use of the word "since," and period of time indicated by a year-year notation. That is a lot to unpack and interpret.
When trying to extract information from a timeline, a reader must be aware of all the chronological conventions that denote quantities and passage of time. These include terms like decades or centuries, as well as notations such as BCE (Before Common Era) and CE (Common Era), or BC (Before Christ) and AD (anno Domini — Latin for "In the Year of the Lord"). The notation ca. means circa, indicating historians aren't exactly sure of when an event occurred. When you're dealing with timelines on a very large scale, they may use the notation BP for "before present" or YA for "years ago." These chronological conventions are not really intuitive for students and can therefore be confusing, hindering their ability to reason chronologically.[11]
The timeline above also demonstrates an effort to represent duration, or how long a historical event or phenomenon lasted, by writing year X-year Y as one piece of temporal data on the line. Not all timelines display duration of events; sometimes they only display points indicating when events begin or end, even though historical phenomena can vary in duration from hours to hundreds or thousands of years. This may be confusing or misleading for students. Even when timelines try to show duration, they can do it poorly. Consider a timeline that uses bars to represent duration — are they using the same scale for all the bars? Say, 1 cm = 1 year? Are they really helping students conceptualize the difference between a 1-year event, and a 100-year event? And have they clearly represented something that lasted 200,000 years, like the time that Homo sapiens survived as foragers?
Duration is one of several temporal concepts — along with periodization, sequence, and concurrence — that historians regularly use to make sense of and study time, but can be really challenging for students to grasp. For example, historians regularly use a device called periodization to compartmentalize the past into different periods, eras, or epochs based on patterns of change or trends that they have identified as significant. Timelines often display events that characterize a historical "period," but the concept of a historical period alone can be puzzling if one does not understand what defines a period, or how it has been determined. Such confusion might be exacerbated by the fact that historians often disagree over periodization schemes. Concurrence, when events overlap in time, is another important temporal concept for reasoning about the past, and one that is not always well represented on timelines. Events on a timeline may appear to be purely sequential, as if events were one after the other, even when they overlapped in real time.[12]
Perhaps one of the best ways to help understand these different conventions and concepts is to have them create timelines on their own, allowing them to grapple with some of the challenges inherent in making visually accurate timelines. And by understanding these conventions and concepts, students will be better prepared to analyze existing timelines, questioning what they show and don't show, and using chronological reasoning to examine how events of the past are related.
