Welcome to the group Laura and other new student members! A couple of tips:
You can set how you receive emails about posts in the group page under Notifications, on the right side of the page. Daily, Weekly, etc. will give you a digest email with all of the activity over the previous week, month, etc. "Immediate" will result in an email to your inbox from every post to the group.
To send a message to the group, use "Create new post" under the Post List. Be sure to hit "Save" at the bottom after typing your message! You'll also see that you can choose to send the message to other groups on localfoodsystems.org as well.
Hope the semester is going well for you, despite the extra challenges of the day.