Your request is similar to what I have here : Send Same invoice to many customers at a go
But the truth is, if you know how to batch create in Manager as explained by @Patch you are good to go.
You can make life easy for you by sharing responsibility. For example, if you have student IDs (customer Code) you can request student to fill a simple google form or something to register for a class/Activity/item/term/semester etc then you could use that information to pull out all the UUIDs of those student in that class from a database you have exported from Manager for batch invoicing.