Version 1.0


This document contains the necessary information to use the GMetrix Common Cartridge files, including URLs, parameters, and use cases. This document assumes basic knowledge of the LTI 1.1 specification, and Common Cartridge 1.3. More information can be found here:


General Information

OAUth Credentials:

The Consumer Key and Secret used for LTI and Common Cartridge are tied to the testing center on the GMetrix side. This means that each testing center in the GMetrix system that needs access to the LTI will need their own consumer key/secret.

You can request your key and secret by logging in to your GMetrix Testing Center, clicking “LTI Resource Lookup” on the dashboard, and clicking “Request Key and Secret” at the top. Once a key has been generated, it can be recalled in the same location.

Obtaining A Cartridge

GMetrix delivers a Common Cartridge on the Course level. When you purchase a GMetrix license that contains resources that can be delivered via LTI or Common Cartridge, a new section will show up on your dashboard for LMS Integration. Click the “Resource Key Lookup” Link, and you will be directed to the lookup page. You can also access it directly here:


That page contains a list of all the resources your Testing Center has access to. If the resource can be launched directly through an LTI link, you will see a resource key. If the resource has a Common Cartridge file that can be downloaded, a Download button will show. Not all of the GMetrix content is available in both delivery methods, and so you may see something like the following:


In that example, you can see some courses are available as a cartridge, others as a direct link, and others are available as both. If you have a request for content to be available in a delivery method that is not shown, please contact us at [email protected] and let us know which content you would like to see in which format.

Cartridge Options:

When you click the “Download” button for a cartridge, you will see the following options:

Default Optional Settings:

If you do not change anything in the settings window and click Download, you will download the generic cartridge for that course. That cartridge will not include any of the settings for your organization, and so is safe to distribute, for example to another teacher at a different school. If you do include any optional settings, the cartridge will then be tied to your organization, and should not be distributed.

Include Key/Secret:

If you select this option, the Key and Secret that is associated with your school will be included in the cartridge. This allows you to skip the step where you configure this in your LMS, and/but also makes it so anyone who uses this cartridge will also be associated with your school.

Use Access Code:

You can enter an access code that was created from any of your licenses into this textbox. If you do, any student accessing resources using this cartridge will have that access code redeemed to their account. This can help the student by skipping the step where they have to get access to the content, but also means that you need to be sure the access code has enough uses for the students that will be accessing the course.

If the access code included in the Cartridge expires or runs out of uses, the cartridge will still work, it will simply skip the access code redemption step and the students will need to get an access code from elsewhere.

Choose LMS:

There are some minor differences between different LMS platforms, and the system accounts for them here. If you are not sure which LMS you are using, select Other.

Import the Cartridge into your LMS

Once the download completes, you can import the cartridge into your LMS.

We have developed some specific documentation on this step for the following LMS platforms:

Gradebook Sync:

GMetrix implements the Basic Outcomes Service defined in the LTI specification. For Assignments, the score will be returned to the outcome URL once the resource has been completed. The sourcedid parameter is used to link the GMetrix resource to the LTI resource in your LMS.  Scores are sent as a percentage, using a decimal between 0.00 and 1.00.

Resources in Progress:

If the student quits a resource without completing it in the GMetrix system, they will be returned to your LMS using the launch_presentation_return_url. This will leave the resource in progress and will not call the outcomes url. The resource will resume if the same launch link is clicked.