You can assign automatically using cohort sync.
1. Create a cohort with the appropriate students.
2. From the Learning Plan template view, the column heading Cohorts has a number value, select the number and the Cohorts synced to this learning plan template page will be displayed.
3. Select the desired Cohort from the down drop list.
4. Select the Add cohorts button.
The ongoing maintenance will only require you to add students to your cohort. All students added to the cohorts will be automatically added to the Learning Plan.