Degrees of an earthquake from 1 to 10

So as I was sitting in Mr. Kay's freshman drama class Mr. Kay is teaching his students about interacting with their environment. He's throwing out these scenarios for them to act out like "Your walking barefoot across broken glass." or "Your walking in waist high jello". And then he decides to make up this scenario on the spot about degrees of an earthquake and what it feels like on a 1 to 10 scale. These poor kids would fall straight to the floor at like 5. And then 10 comes along and I turn my head for a split second and I hear them all fall to the floor. I wasn't sure if I should be worried or if it was o.k to laugh. Luckily they were all o.k and it was safe to laugh.