Final answer:
The most likely conclusion is that the window in Mrs. Scheck's classroom was broken from inside the room, as indicated by the glass found on the inside and none outside.
Step-by-step explanation:
The best conclusion that can be made from the scenario where glass is found on the floor underneath the window in Mrs. Scheck's classroom and no glass is found outside is that the window was likely broken from inside the room. This hypothesis is supported by the Broken Windows Theory, which, although mainly a crime theory, also helps us understand the spread of broken glass in an environment. In this case, the absence of glass outside the window suggests that the force that caused the break came from inside the classroom. An outside break would typically scatter some glass outwards due to the momentum of the object breaking through the window from the outside.