If your students are completing work and this is not showing on your Teacher Dashboard it could be for a couple of reasons:
They are using the wrong account
Make sure the student is using the account linked to your class. You can check the correct username by going to Manage > Students and selecting your class from the dropdown menu. The username will be displayed there. Confirm that this is the same username the student is using to access Doodle, as students sometimes create duplicate accounts. More information on checking the account they are using can be found here.
They are using different devices
Children can use different devices to Doodle. If they are switching between devices they just need to make sure:
They have an internet connection while working so that their work syncs to the server. If they need to use Doodle offline, they just need to ensure they use the same device while offline. Then, once they regain internet access, they should log in on that same device to allow the work to sync with our server.
If students are still having problems with work syncing/saving this help centre article is useful.