Perhaps more interesting for teachers is that apps come alongside something called "idea sparks," which are essentially editorial pieces of content written by people in education that give examples of lessons to use the app in the classroom. The Hub also has a host of filters for searching for trending topics, subjects that teachers or students may be looking to emphasis or apps appropriate for different age ranges. Google says that both the featured apps on the App Hub and idea sparks will be updated on a quarterly basis going forward.

The Google Education team has a number of other improvements they're rolling out to the Classroom product in advance of the next school year, as well. Last year, Google rolled out a beta of Gradebook, a master place for teachers to keep track of a class's assignments and grades. That's ready to come out of beta now, but Google's making a big change: it can now hook into the school information system (SIS) of choice, something that'll keep teachers from having to enter grades both into Gradebook as well as the SIS. Obviously, if Google wants this tool to take off, teachers can't be expected to waste time entering grades twice.

Another new tools educators have to look forward to is custom grading rubrics (or scoring guide) that can be included with each assignment so that students know exactly how the assignment is being graded. And while teachers are grading, they can now create a "comment bank" of feedback that they give often so they don't have to type out "misspelling" over and over again.

Finally, a "locked mode" that teachers can enable on Chromebooks manged by a school is coming out of beta. That's a quick way for a teacher to keep students from using their Chromebooks in ways they shouldn't be (like looking up answers or chatting with classmates) while taking a test, for example. None of these are radical changes, but as Google Classroom continues to mature (it's now used by 40 million teachers and students), this kind of polish is important if Google wants to keep its education customers happy.