The advantage the iPad lies directly in the App Store. There are creation apps, maker apps, and coding apps that just aren't on Android. Software developers look at both the depth of iPads on the school side, but they also love k at which one will hit consumers first. IPad continues to win in the tablet market, so that's where developer interest lies, and I don't know that I see that changing.
For a Chrome Tablet to be successful, they have to get those difference-making developers to do it for iPad. To me, that means it can't just be school facing. The tablets have to hit the consumer market. I also think you won't see schools shift from the actual Chromebook because touchscreen Chromebooks come in at a similar price point.
I think the Chrome tablet may be much to do about nothing. Unless something drastically changes, IOS is where developers are going to go first because of the consumer market. When they come to Chrome, they are going to figure out a solution for clamshell Chromebooks first because that's what many already have and will continue to buy. That app may work with the tablet, but it will never be a priority.