How to prove abuse at school with young children?

Forced education *is* the abuse to young children.

Talk to other parents who have children in his class. Your son is telling you it happens to other students. Talk to the parents.   

Pop in unexpectedly at the school for a check. 

There is something there he doesn’t like. It could be being away from you to another child he isn’t getting along with.  Could be the tone of the teacher’s voice. Ot that rules are very different at school from home.

Where do you live?  Personally I have never had or hears of a school tell a parent outright that they spoil their child. They may think it, but would never tell a parent that.  

Stick to your gut,  move him to a different school if need be.

My guess is that there's something else he doesn't like at the school. Maybe one of the kids has been mean to him. You need to talk to the teacher about this. Kids get a lot of fantasy input from tv and movies these days. He's telling you what he thinks will get him out of going to school. 

Many parents, especially with their first child, want to believe that their kids are always angels, and they would never make stuff up or lie. Please listen when I say that KIDS LIE! Yes, all of them, even yours. I assume he’s maybe 4 or 5, and he may be confusing reality with fantasy if he’s not just telling outright lies. He may have gotten the idea from a movie or book, another child, or maybe he overheard someone making a joke. I’d say it’s very unlikely that he’s telling the truth, although he may truly believe what he’s saying. 

If you want to put this to rest, there’s a few things you can do. Start by taking him to school and pointing out this “monster closet.” Ask him to describe it in detail, and tell you what’s inside it (besides monsters). Then have him show you what’s inside. This will at least give you an idea if he’s ever even seen the inside of the closet. Just keep in mind that knowing the contents of the closet doesn’t mean his story is true. But it’s a good way to see how far he will go with this lie or delusion. 

You could also speak to some other parents and their children about what goes on at school. Without putting any ideas in the child’s head, ask them about the rules and the punishment for breaking those rules. Ask where the teacher sends kids who don’t follow the rules. If the other kids don’t know anything about this monster closet, then you can assume it’s not true. There’s also a small possibility that the teacher told the kids about the monster closet to get them to behave, but doesn’t actually put kids in there. 

If your son still won’t let this go, you can try sending him to school with a hidden camera or microphone on his clothing. There are spy cameras and nanny cams that are very small and easily hidden. Make sure your son doesn’t know about it. This will let you know exactly what happens once the parents leave. 

Once you confirm his story isn’t true, you need to tell him that you don’t wanna hear about it ever again. He’s either confused about something, or he’s lying because there’s another reason he doesn’t wanna go to school. It’s possible he’s making up stories because he doesn’t wanna tell you what’s really going on. But do not reward his lies. He may just be doing it for attention too. Whatever you do, do not give in to his tantrums. If you validate his bad behavior, he will keep doing it until he gets his way. 

Perhaps you just need to take your kid to a different school. If he continues speaking about the closet at another school, then you'll know he probably isn't telling the truth. Are there other parents experiencing this too? All in all, I would consider finding a different school if it's possible for you.