Allow your students to try some of the lessons for free with the Trial Courses feature.
How to enable Trial courses?
Go to the STM LMS menu and find the Addon tab.
Find the Trial Courses among the list of addons and enable it (1). Next, open the setting s window. Just click on the appeared Settings badge (2).
Enter the number of free lessons you want to be in the course and Save Settings.
Now, when you create a new or edit an existed course (STM LMS > Courses > Choose a Course > Course Settings) enable Trial Course feature by dragging the slider to the right.
Saved settings (number of free lessons) will be applied automatically to the course.