Since students may not have access to email at home and because some schools do not issue school email accounts, one solution may be to create sub accounts.
How it works:
You sign up for a Gmail account. This is your teacher account, not a personal email account.
Add new other email addresses to the account in the settings menu.
Each student should be assigned a sub account linked to your teacher account. To create these sub-accounts, add a plus sign and the student's name after your name and before the @gmail.com.
krajiceks @ gmail.com
krajiceks+stephanie @ gmail.com
For better instructions, check out this link.
* Remember to check your school's Acceptable Use Policy and to review Google's Terms of Service before jumping in. Sending home a letter of intent / permission slip isn't a bad idea, either.