If your school has an institutional account, joining is easy.
New to ThingLink
If you don't have a ThingLink account yet, you will join the organization at sign up. Go to www.thinglink.com/edu and register for a free teacher account. On the sign-up page, make sure to enter your school invitation code. If you do not have this code, ask the administrator who set up the school account.
Already on ThingLink
If you're already on ThingLink it is not too late. Head to your Groups page (upper right menu > Groups link). On the next page, choose the Groups tab and enter the invitation code in the field on the bottom. Then click the Join button. After clicking Join, you should see a dialog box asking to confirm the request. Click this button. Your administrator will need to approve your request.