For anyone that none of the unblockers work try this method. 

Step 1. go to chrome://settings/signOut/ 

Step 2. Click on turn off 

Step 3. Go to chrome://restart (save your work before doing this because it restarts) 

Step 4 (optional). If you want to be able to use google things like google classroom then go to tinyurl.com/addsession 

Step 5. (continues step 4) sign in to your school google account (if personal is allowed then do that) And you can now do anything