Open the Gradebook
Click on the Reports tab
Click on Student Roster
Select Export (CSV)
Select Student Name
Select Guardian Email
Click Run Report
Choose Open report
*Repeat for each class
You can save and use the Excel spreadsheets that are created, but I prefer to copy each class into one Google Spreadsheet.
Notice that some students have multiple parent email addresses. They may be separated by commas or semicolons.
Gmail will allow you to copy and paste the list into the To field with commas and semicolons.
Outlook will give you errors due to commas and semicolons so there is a little more work to do if you want to send emails from Outlook.
You can use Split to create lists that will work in Outlook. Type =split(B3, ",") into the cell next to the first email. Split needs to know what you are trying to split; in this case it is cell B3. Then it needs to know what you are using to indicate where it should separate; in this case a comma.
Then you can drag that formula down the list by dragging on the little blue box on the bottom corner of the cell with the formula.
For the emails separated by semicolons, you will have to change the formula. Just replace the comma in the formula with a semicolon =split(B3, ";")
Now you can copy and paste the cells containing the separated emails into the To box of an Outlook email.