This article covers the line chart task type.
For a general overview of tasks and what they can do, see An introduction to tasks and for general instructions on how to add them to your course, see How to add a task to your course.
Overview of the line chart task
In the line chart task learners are able to create or modify line charts. You can pre-populate the chart with as much or as little data as you’d like. For automarking you can specify what points you expect where or you can leave it completely open.
When to use a line chart task
The line chart task is useful for helping learners to practice graphing, correcting incorrect points on a graph, or doing the heavy-lifting of some point-plotting for learners leaving them to just complete the graph or making predictions. Let’s take a look at a few examples.
Example 1: Predicting the shape of a graph
In this example we give learners a partially completed graph, then ask them to predict the shape of the graph after 150s.
Example 2: Spot the plotting mistakes
In this next example we ask learners to identify the mistakes in the graph and correct them.
Example 3: Plot your own graph
In the example below we leave all the points on the chart at zero for learners to make their own graph.
The Line chart task vs. the Plotting task
The Line chart task has some overlap with the Plotting task, in that you could really use either when you want learners to create their own line graph. However, we find that although it’s a tad more complex for learners to use, the Plotting task is a little more flexible in how you can let learners plot the points. So if your learners are used to plotting graphs, we’d typically advise using the Plotting task instead. Choose the Line chart task when you need simplicity.
How to create a line chart task
All tasks load with an example task to give an idea of what each field is for. To add your own task details, you can type over the existing content in the fields or select Clear task content, to start completely fresh.
Standard fields
This task has the standard fields/options that all tasks have.
At the top:
Question: Where you set the main question/task which tells learners what to answer or do.
And at the bottom:
Hint: Add a hint to give pointers or clues to give learners extra guidance to complete the task. Learners can choose to See hint to allow them to get this help “on demand”.
Feedback: Add feedback to give learners an automated response when they submit the task. See Writing feedback for tasks for pointers and ideas.
In between the top and bottom standard fields we have the following areas and fields.
How to set the graph details
Here is where you set the graph labels and set the points that learners can drag.
Name: Adds a graph title.
Max Y-Axis: Sets the maximum height of the Y-axis of the chart.
X/Y axis label: Adds labels for the X/Y axes.
For each point in the chart you can set these fields:
Label: Adds a label for chart bars (the space between gridlines).
Value: Is the initial value the point will be set to when the learner sees the task.
Interactive: Allows learners to interact with the point. Turn this option off if you don't want students to be able to move the point.
Select +Add to add more points to the chart.
Select the delete icon beside a point to remove it.
How to set the correct answer(s)
If you want the task to be automarked, you can set drag each point in the chart to its correct value.
If there are other correct answers, use the + to add alternative answers.
As seen in the examples, you can also choose to not set a correct answer. In which case, the task will not be automarked and the task will be allocated the complete/incomplete with feedback marking template to allow facilitators to manually mark the task (if desired).
Other options
You can also specify additional options:
Snap to grid: Snaps the point to the nearest grid line when the learner is moving the data point.
Threshold: Sets the distance a point can be from the valid score and still be marked as correct.
Add point: Allows learners to add points to the chart and interact with them. When enabled learners will see Add data on the left side of the chart toolbar. By selecting it they will be able to add a new point.
Ignore order: Allows points order to be ignored.
Authors can set additional options that can be available for learners when interacting with points:
New Point Name: Enables the author to specify the default name of all new data points added by the learner.
Resize point: Allows learners to resize points on the chart.
Edit point label: Allows learners to edit the data point labels.
Delete point Allows learners to delete a data point.
Order point: Allows learners to reorder the data points.
Show axis gridlines: Determines whether axis gridlines should be displayed on the chart.
Font size: Controls the size of the font for items in this task - Small(11px), Normal (14px), Large (17px), Extra large (20px), and Huge (24px). We recommend Large for most purposes.
Graphing accessibility
People using only a keyboard and/or using a screen reader can interact with our graphing tasks.
Keyboard navigation
People using only a keyboard can tab to the menu and navigate the menu items using arrow keys. Options in the menu can be selected with either Spacebar or Enter.
Tab will take them to the graph plane where they can navigate the grid using arrow keys. Points can be plotted with Spacebar or Enter. Pressing Shift-Tab will take the learner back to the menu to select further options.
Note: at this stage, the label tool is unavailable for keyboard-only users.
Screen reader navigation
People using screen readers can use the same keyboard navigation described above.
When navigating to the graph, the screen reader will describe the content of the graph including the axis values and any background shapes.
When navigating to the menu, the screen reader notifies people of the keyboard controls to interact with the menu. All menu options are announced as they arrow through the options.
When tabbing to the graph plane, the screen reader notifies people of the keyboard controls to interact with the graph plane. As they navigate around the graph the coordinate locations are announced and as they plot points they are notified of the plotted point and its coordinate.
When people press Shift-Tab to go back to the beginning of the graph, they are notified of all points or shapes plotted.