If your class was manually rostered and you are its primary teacher, you can change its name by clicking on the vertical dots below the class, then on Settings, and finally on Rename.
⚠️ There can't be two classes with the same name in your school ;)
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If you are the co-teacher and the class was rostered manually, you will need to ask the primary teacher to rename it.
If your class was rostered via Clever or the Renaissance Platform, you will have no option to rename your class.
For Clever: Your school administrator will need to update the class name on Clever, and then you will need to click on "Re-sync students" to update the name on Lalilo.
For Renaissance classes: your classes and students are added and edited automatically, so please contact your administrator if you need them to be updated.