Log in to Levebee at www.levebee.com (or register at www.levebee.com if you do not have an account yet)
After logging in, select the Settings section from the menu at the top right
Select the student (child) to whom you want to add a license and click on the Licenses button next to it (or create a student first if you do not already have it by clicking on Add student)
At the bottom of the page, in the licenses selection, enter the activation code and click Confirm.