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In Box 2 (Return to Terracotta), you are provided with a return URL. Your custom web activity should redirect users to this return URL, and Terracotta expects that your custom web activity will append two URL parameters: (1) launch_token, and (2) score. If “score” is omitted, Terracotta will assume that the submission will receive the maximum score.
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Responsibilities of the Custom Web Activity
When a custom web activity is integrated in Terracotta as a LMS assignment, your activity is responsible for supporting student learning, honoring the assignment settings set by the teacher, and reliably returning students’ outcome scores back the LMS. The custom web activity is also responsible for presenting a learning activity that is accessible, and the designer of the custom web activity should be familiar with web accessibility standards.
Launch Parameters
The following variables are automatically provided to the custom web activity as URL parameters:
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Terracotta will not accept a score for a launch token that has already been used, nor will Terracotta accept a score for an activity that has 0 remaining attempts.
Best Practices
Record Granular Data: Your custom web activity will be responsible for a legitimate academic exercise, and it should keep records of users’ interactions, responses, and submissions. By doing so, your custom web activity will help ensure the integrity of students’ coursework.
Check if the Launch Token has Previously Been Used: When configuring a custom web activity in Terracotta, there is a checkbox: Tool allows students to view past submissions. If this box is checked, Terracotta will assume that the tool is able to display a past submission to a student. In this situation, if the external webpage receives a launch token that has previously been used, this indicates that a student is attempting to review their responses from a past submission. Check if the launch token has previously been used, and that the anonymous_id and assignment_id of the current launch matches the anonymous_id and assignment_id of the past submission associated with the launch_token. If so, the external page should display the data from the past submission associated with the provided launch token, with no interactivity.
NOTE: There is one reserved launch_token: "0000000-0000-4000-a000-000000000000". This launch token is issued by Terracotta when previewing external integrations.
Communicate When There are Limited Remaining Attempts: When the teacher has placed restrictions on the number of attempts that a student may submit in response to an assignment, it may be helpful for the custom web activity to communicate this to the student (e.g., if there is only 1 attempt remaining). If there are unlimited attempts available to the student, remaining_attempts = u. A custom web activity will never need to handle a situation where remaining_attempts = 0, because in this situation, Terracotta will not generate a launch_token and will not launch the student into an activity.
Respect Due Dates: Consider warning users when they are accessing the webpage after the due date. Submissions made after the due date will be delivered into Canvas, but will be flagged as late.
Score Calculation: The custom web activity is responsible for determining the student’s score on the activity, which should be returned to Terracotta as a URL parameter value with the name “score.”
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