Should children be suspended for taking toy guns to school?

absolutely and arrested too.

It depends! Do they use them as weapons or to play games? Is is an air rifle, a water gun, a pellet gun or a plain replica that is not dangerous? Are they used to scare people? If it is a toy used as one, it should only be kept under lock until the end of the day and be returned home with a note stating that toys in general are not allowed in school. If it is used otherwise, it should be only handed back to the parent unless it was used as a weapon than it should be taken away for good. Also, suspension would be a good consequence especially when the student is older. The older he or she is, the more severe it should be.

Most of the time I would say yes. But if it goes with your Halloween costume on the day your school celebrates you could have it so long as it doesn't shoot projectiles of any kind.

No but the guns should be taken into the Teachers possession and the parents asked to make sure they do not take them again.

This does of course depend on the age of the child. Above about 7/8 I think it should be mandatory for them to have lessons on what is NOT a good idea to carry.
In the climate of shootings people are very twitchy and young teens and even younger boys could have toy guns mistaken for the real thing.

No, why? It's a piece of plastic. Have we become such pussies that a harmless toy warrants a suspension from school? As a society we need to stop taking so many reactionary measures and start taking more precautionary measures (ie teaching children about the dangers of guns).

Of course not. Toy guns were a prop at our school for the drill team or the such. It even had a fake bullet in the chamber. The drumstick may have made a better weapon. The trombone for sure.