Go to the Wi-Fi section of Settings.
Tap and Hold on DoE_Student
Tap on Manage network settings
You'll see a few options.
For EAP method, select PEAP
For Identity, type in your school email address
For Password, type in your school password
For CA certificate select Don't validate
It should look something like this:
From here you can press save, and if it doesn't connect automatically, tap on DoE_Student again
The phone may prompt you to sign into the network, if it does, tap DoE_Student again
If not, visit http://webauth.education.tas.gov.au/ (it's recommended to bookmark this to make it easier to find later)
The phone may also take you here automatically
You should end up on this page:
Type in your school username and password in here the same as you would signing into a school computer and press Login