Here’s a nifty little thing in Google Calendar that many people may not know about. They’re called appointment slots, and they can be incredibly useful and simple to set up.
Add a new event
First, you’re going to open up Calendar. You can have it in day, week, month view, doesn’t matter. Click on a time slot, and the Event box pops up. Look over to the right, and you’ll see “Appointment slots”. Click on that, give it a name and set the duration. If you select more options, you can set up a few more options. Next to the slot duration, you can click the pulldown tab and select Every Weekday so that you don’t have to create a new appointment for each day. This is useful if you’re allotting the same time slot every day.
Open and share the Calendar appointment page
Because you’ve selected Appointment slots, this has a unique aspect. You’ll see a link in the Event box that says “This calendar’s appointment page”. 
When you open that up, you’ll see another calendar page, but this one has clickable buttons. Other people can now click on the buttons to set up appointments. Just share the link to the appointment page, and anyone can click to sign up for a slot.
This could be really useful for allowing parents to set up conferences. What I like about it is I can set up a tutoring schedule. I can have slots open before and after school for students to sign up to come in for tutoring or for extra time on a computer. You can set up multiple slots for the same time slot if it’s something like tutoring and you want to allow multiple students to come in at the same time.
A few tips
A couple of tips. First, you’ll probably want to create a separate calendar from any others you may be using. This calendar will be public, so you don’t want your entire calendar available for all to see.
You’ll want to make this calendar accessible to students and parents alike. Click the three dots next to your calendar and click on “Settings and Sharing”. Click the box to make it available to the public.
You’ll want to make sure you share the appointment slots calendar, not the calendar itself. They’re two different things. When you click on one of the appointment slots, you’ll click on the link to go to the appointment page for that calendar. This is the link you want to share.
Share the link with students and parents. Have it available wherever you want people to be able to access it, and then you won’t have to worry about the scheduling. If someone needs to sign up for a time, they can do it themselves. Simple, easy, and it takes some of the organization off of you.
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