If you have an individual account on Remind, the best way to reach your entire school community is to create a class for school-wide messaging.
You can manage participants the same way you would for any other class.
You can also archive the class and reuse the class code if you want to start fresh at the beginning of a school year.
If you're an administrator with a School or District Plan, school-wide classes can be automatically created from roster information. When you use the Admin Console to manage people in your school or district, any changes you make will be reflected in your school-wide class.