School Forms are viewable from behind the App. School Forms are attached to the User, and when the User logs in, they can see the "You have forms to review" banner.
School Forms cannot be added to the Public Website. This is because they are attached to the User, Parent of User, or Both. This means the User needs to be logged in to see the School Form. The School Form is customized for each based off of the Constituent Information of the User which is why there is no public URL access.
Instead you can use Custom Forms or a Event Registration if you want to display a Form on your public Website.