What do your instincts tell you? And where did you get the program you're using? Did you develop it yourself, or is it one you were told to use?
Some strong recommendations - get your hands on two books especially. "The Explosive Child" by Ross Greene, and "Son Rise" (not sure of the author; Google it and you will find it).
The first book is one which has been a big help for a lot of us on this site. The second one may help you with Bob, where you both are now. The gist of it is, with an autistic child you begin by working with him where he is now. Find what he wants to do, sit with him and do it yourself while you are beside him. Meet him where he is, and as he begins to interact positively, work from there.
We were lucky with difficult child 3 - his 'fetish' was letters, number, music and words - anything written down. We used this to reach him and help him understand the concept of communication.
A lot of positive reinforcement, a lot of support, avoid punishment or any negative consequences. If he hurts you or attacks you, walk away and leave him on his own. If he quiets down, come back into the room and do what he is doing. If that involves lining up cars, then get your own cars and line THEM up. Don't use his, don't encroach into his space, simply make your space a parallel one beside him.
Also important - recognise that somewhere in there is a child who is probably highly intelligent but VERY frustrated and angry. You're asking him to do something which is making him angry - why is that? Is he getting angry because what you're asking is too incomprehensible for him at the moment? Or is he getting angry because you're asking stuff he feels is totally irrelevant?
Autistic kids do not suffer fools gladly, and especially in their earlier development will only see the world as THEY want to see it. Incredibly egocentric. Socially - like babies; the world and its inhabitants only exist to meet their needs, which we must be able to mind-read. But in time, babies grow. Autistic kids will also, once you can reach them and show them the way through.
Something else we found with difficult child 3 - and this could vary from other autistic kids - despite his limitations with communication (in the beginning), he HAD to learn EVERYTHING at once. You couldn't break it down into component parts, as they are always telling us to do, because this confused him. For example, he learned to communicate by seeing the word written down, a picture of that word, hearing the word spoken, being in contact with what the word was, and eventually using it. ALL AT ONCE. If we just tried to say the word he didn't understand. If we wrote it down he eventually worked out to read the word as a meaning for the object, but had no idea how the word sounded. For example, the word "stop". He saw it on stop signs in traffic signs. The signs were red and he knew that red light meant stop (even before he knew 'red' or 'stop'). So I wrote the word in red, shaped like a stop sign, read the word to him aloud, and as I said the word (as we were walking along) I stopped walking. I then said, "go" and set off again. We made a game of it and within minutes, he could say the word and knew its meaning. He also could read it in any location. And I am not kidding about "within minutes".
I made little books for him - disposable, our of a sheet of paper folded in half, half again and again, then stapled down one side (tape over the staples for safety) ands pages cut free. I would draw a picture and label it carefully. I drew his picture on the front, with his name. If he tore the book to pieces or lost it, I could easily make another one. As he 'evolved' I made new books to enlarge his vocabulary.
At the time difficult child 3 was minded on some days by a lady with no training, just instinct. She adopted my book and did her own thing with it, putting in words she chose (which I wouldn't have; but that was still OK) and also deciding it was time to teach him his colours. Because the book had been working for us, it was easy to slide from nouns into colours. She used coloured pencils to colour a patch, then wrote the name of the colour in black (because some colours are just too pale). She supplemented the book with showing him the pencils themselves and letting him scribble on plain paper with them, each time saying the name of the colour.
By the time I collected him, three hours later, difficult child 3 had gone from not even understanding the concept of colour, to knowing the names of about seven or eight colours - reading them as well as identifying them.
At that time we had no idea he had autism - he didn't even have a diagnosis of language delay, he was only two years old. But I had been concerned for some time and was trying to sort something out myself, in the absence of any official help.
Anyway, I just wanted to show you that different kids learn in some surprisingly different ways and until you work out how YOUR kid needs to learn, you will both be frustrated.
Try to not get too upset with him when he gets angry and frustrated - how else can he communicate how he feels? Of course it's not right, but he doesn't yet know any different, he's too young an inexperienced to be able to get his message across more appropriately.
And also - don't try to change everything about him, all at once. Just as ANY kid who is learning one skill often backslides elsewhere, if you push too hard in too many areas you may see deterioration elsewhere. Don't panic.
difficult child 3, once he gets the idea of a topic, can learn it FAST. Or it can be mind-numbingly slow. It depends on whether he's ready, frankly. And how it's presented to him.
If you could meet difficult child 3, you would have hope. If you read "Thinking in Pictures" by Temple Grandin you will know what I mean - difficult child 3 was non-verbal, had no idea of language (which meant he didn't know his own name or even that names existed; I could be calling him and calling, thinking he'd got lost, been run over, and find he was sitting under the table, playing). He was a physical handful as we had to push and pull to get him to do what we wanted. He was fussy about certain textures, avoiding some and hooked on others. He HAD to have a towel with him, especially when he was tired. He couldn't talk but could mimic any sounds he heard including the words of film and TV, as well as songs on the radio. He had little or no understanding of what he was repeating. When caught up in something he was obsessed with, we had to leave him and wait until we could persuade him to move on.
He would chase birds when he saw them, regardless of consequences. He was obsessed with water, falling objects, round objects and trees. He would lose himself in music, so we taught him to play the piano, connecting sheet music to his knowledge of the alphabet by labelling the piano keys with letters and then writing the letters in sequence so he could learn his favourite tunes. That rapidly progressed to him reading sheet music.
What we were doing - we were meeting him where he was. As I said, we were lucky that he happened to be obsessed with something useful like letters and numbers, it opened up doors rapidly.
difficult child 3 has a good buddy who is also autistic. Sheer fluke - he's a neighbour. And a few years younger. Not as severe, he's coping in mainstream. And now medicated, doing brilliantly. It was as if he was asleep before this. difficult child 3 has been medicated since he was 3 (I know it sounds horrible) and it was the best thing we could have done. His mate - he's 9, just started on Concerta.
And about 'waking up' - difficult child 3 loves game shows. He likes "Are You Smarter Than a Fifth Grader?" but because he had poor language skills for the first few years of school, he has gaps in his knowledge. He can answer the more senior questions, but often misses the 1st Grade ones. Today he's been working on Biology (flowering plants) and we were discussing experimental theory, the definition of uncontrolled variables compared to controlled variables. But he still struggles with more basic knowledge. In English he's brilliant at spelling and grammar but has great trouble with inferred meaning and questions such as "What do you think the girl was thinking at this point?" because it requires theory of mind, which he is still developing.
But he is getting there. I took him to the bank on Friday, to bank a cheque that had come in. He worked out what to do, he waited his turn, he explained to the bank teller what he needed and followed her instructions. He managed very well. In fact, he managed better than difficult child 1 does, in similar circumstances.
So cheer up, there is plenty of reason to hope and to be glad in this child. He will have an innate honesty, as well as deep feelings and loyalty. You will see this more as he gets older. And somewhere in there is a boy who wants to learn, but is very frustrated at how confusing and annoying everything is. As they learn to meet us, they become eager to please us and to blend in.
Keep us posted on how you get on.
Marg