Checking out books to your students in Booksource Classroom can be done directly from the Teacher's Page of your library.  

To check books out for your students, login to your Teacher Dashboard and go to your Library. Find the book you wish to checkout by searching the Title, ISBN, or Author.  Hover your cursor over the book you wish to check out and select the blue checkout button.

A new box will pop up displaying the available copies of the selected title.  Type the students name next to the copy you wish to check out, and select Done to finalize the checkout.

Student Page: 

If using a barcode scanner:

Your students are able to use a barcode scanner to search the book they wish to checkout.  Click your cursor into the Search bar, and scan the barcode on the back of the book.  This should bring the student directly to the title where they can proceed with checkout. Other options include searching by title, author, or keyword.

In the below example,  the Teacher has required students to select the condition of the book upon checkout.  Teachers can opt to have students select Condition, Copy, or Rating upon checkout.