My attitude changed when I realized that the student was part of the AG program and that the different students were allowed to eat the eggs. The person who did the egg stealing has been described as slow, so I was not sure if he was aware of what eggs were available to eat. The OP also said that she talked to her teacher and was going through them.
What the other student did was wrong. But really, if an apology and possibly money is given for the egg, then this is a life lesson. The student that took the eggs needs to make some sort of restitution, but does not need to go to jail. As the OP's chickens were part of the program, they may not have understood.
Some posters on here have suggested that this kid DIE for doing this. Come on. Get real. Someone else on here suggested in a different post that the post office employees should die. Suggesting that a child or post office worker die, is crazy. It is unibomber talk. It is insane. As insane if not more than eating a baby chick. Though the thought of that is horrifying.
As a teacher, I don't wonder what is wrong with kids. I see lots of great kids. Still kids can make a mistake. If dealt with compassionately, fairly and with consequences, they can grow into great adults.