All depends on how it was done. If he put the pencil, for instance, on the throat of another kid then the suspension is motivated but if he just played a little bit pretending he was holding a gun, well, since when kids are not allowed to play? I understand that firearms are a problem in the US: just make them illegal like everywhere else in the world so there will be no need to become paranoid.
There's a huge difference between a 7 years old kid pretending he has a gun and a 16 years old doing the same thing. The first one is most probably just playing while the latter is maybe trying to threaten someone. Let's allow children to play, like they always did.
America is motivated by fear to the point that it makes them blind and irrational. You are right about the age comparison. Getting the child to say sorry and not do it again should be enough but suspension, come on we;'re not communists.
Even if he threatened someone the suspension is ridiculous: he is 7 years old! At that age, kids are not aware of what they do. Punishment is a defeat. Is like saying: "I'm not able to give you an education so I will just punish you to get out clean". He is a child, we are the adults. Our role is to explain children what is right and what is wrong and, possibly, why that is right or wrong. Which is the word that always goes with "School"? "Education"! If a school can't teach a 7 years old child to not use a pencil as a gun, well, they should shut down that school.
I still think that we should educate children rather than punish them. After all, he was pretending a pencil was a gun which is still playing. In my opinion, if he did that during the lesson time, they should have scolded him and that's it. If he did it in the school yard or during the resting time, nobody should have said anything. I can't count how many times, as a kid, I played with a branch or a pipe or a broom pretending it was a rifle. My nephew, which is 5 years old, always pretends to shoot me with a machine gun and I pretend to die when hit. These are not criminal acts: its children playing.
I agree with Brunconero, it all depends on how the child was 'playing' with the pencil. Suspension is too far. What little boy has never played pretend with firearms. Heck, my 6 year old nephew keeps pleading me to get him his own NERF toy gun every birthday and/or Christmas for the past couple years.