Several piece of advice:

First, shift the way you’re thinking about this.

The problem before you is how to do right by a kid in your care. Thinking in terms of wanting to avoid doing something wrong and messing the kid up for the rest of his life is going to make it harder for you to do right by him.

You’re going to do things wrong (you’ve done things wrong in every teaching job you’ve had, it comes with the territory); and it’s going to be important for you to acknowledge and fix your mistakes. Making possible mistakes, even serious ones, a referendum on whether you are a good person, makes it a lot harder to do right by others. I’ve written about that before, here.

Treat him as a person

• Almost universally, autistic people are treated as though they aren’t quite real, especially by caregivers
• Often, they think of this as looking past the autism to see the real person
• But the autism is part of who he is.
• Don’t attribute some things to him, and others to the autism. He is real all the time.
• He is a real person. Already.
• Your job is not to cure him. Your job is to support him and help him to develop his abilities. Learning to do more things will not make him any less autistic, nor should it.

Forget everything you think you know about the difference between autism and Asperger’s syndrome:

• People whose diagnosis is Aspergers syndrome are autistic
• Autistic people who can speak are disabled
• There isn’t actually any fundamental difference
• Except that people considered autistic are often seen as incapable, and people considered to have Aspergers are often seen as faking their difficulties
• Assume disability and ability, and that you will have to figure out how that works for the person you’re working with

Learn how he communicates.

• All autistic people have some sort of atypical communication
• Some autistic people are really good at hiding it, and looking normal at the expense of understanding what is going on.
• Autistic children, particularly boys, often pretend to be acting out in order to mask disability. Be mindful of this possibility.
• A good percentage of the time, when autistic people repeat things over and over, they are trying to communicate something and aren’t being understood. Be aware of this, and learn how to make communication possible in this situation.
• If he seems not to understand something, do not get angry and assume he’s just being defiant or lazy
• Some things are really really hard to understand, even though they seem simple to people with typical development
• For instance, an autistic child who has been isolated might find fiction other kids their age understand completely incomprehensible because they can’t relate to the experiences and relationships it describes

If he makes repetitive motions, assume they are important:

• A lot of autistic people rely heavily on motion to think well
• Or to communicate
• Or to understand things
• Or to find words
• Or to regulate themselves.
• If you prevent an autistic person from making repetitive motions, you’re probably also preventing them from doing things like understanding what’s going on, communicating, and learning self-control and interaction.
• Do not value a typical affect over learning and communication.
• Do not say “quiet hands” for any reason ever. (Unless you’re saying something like “people shouldn’t tell you ‘quiet hands’”)

Do not make him follow rules the other kids are allowed to get away with breaking

• Because that’s unfair, and humiliating
• And it also prevents peer relations
• It also prevents him from learning how rules actually work, which is a vitally important skill, especially for people who are likely to spend large parts of their life subject to arbitrary decisions made by people with too much power over them

Do not confuse him about consent, and help him learn what consent is

• If something is an order, do not phrase it as a request. Doing so teaches people to be incapable of saying no.
• Ask a lot of questions that actually are requests, and go with what he says, even if it’s not the answer you wanted.
• If he always says yes when you ask him things, assume this is because he has been taught to be incapable of saying no
• Ask questions in ways that remind him that saying no is possible
• Or questions in ways that don’t seem to create a compliant option and a defiant option at all.
• For instance “do you want to stay inside today, or would you rather play on the swings?”
• But questions that are real. Not forced choices in which each option is basically compliance.

Support him in navigating the difficult and often hateful world he lives in

• Do not make him play with kids he dislikes, even if this means he doesn’t play with anyone
• There are worse things than being alone. Being surrounded by people who everyone insists are nice and your friends, but who actually don’t think you’re real or treat you well is much worse than honest loneliness.
• It’s possible, and likely, that there are very few kids, or even no kids at all, in his group who it is a good idea for him to spend time with
• And even if you think he’s wrong about this, it’s a decision he should be making for himself (and his judgement is probably better than yours)

• When kids or adults do bad things to him (and they will), you usually won’t be able to make them stop. You should tell him that what they’re doing is wrong, and that it’s not his fault.
• Knowing that it’s wrong, and that others know it’s wrong, helps a lot.

Some things you should read:

• Ballastexistenz From the beginning. Every post. It has a lot of fundamentally important things about power, and dehumanization, and about seeing people as real. This blog has a lot of the best things that have ever been written on this topic.
• Rolling Around In My Head is also a really good blog, written by a disabled man whose professional work is supporting people with disabilities. He says a lot of things worth knowing. Also his book Power Tools is important for understanding how this power dynamic works – and your environment and training will put pressure on you not to understand it.
• Loud Hands: Autistic People Speaking is a really important book about autism and the world written by insightful autistic people. Buy it and read it and understand it, and it will help you to do right by this boy and others