Go to Manage Batches link in the Courses home page.

Once the class/course is selected from the drop-down, choose the batch transfer option next to batch name. 

We need to choose the students and the batch to which they need to be transferred. If some of the students don’t meet the eligibility criteria to be transferred to higher classes, the check box needs to be unchecked and that student will remain in the current batch.

Once it's saved, the selected students will be moved to the new batch.

For more clarifications, please watch this.