Is there something else he likes more than food? For my first few lessons my dog wouldn't eat at all and spent most of the time on edge and cowering behind me - even with all the space between us and the other dogs/people - alas at 15 metres, her safe space, i cannot hear the instructor. So i stuck purely to calm/quiet praise and patting. But each time she was a little less stressed when "nothing happened" and started looking around as she got used to seeing the same dogs/people every week. By the 4th-5th week I could start rewarding with food. She wasn't relaxed by any means, but it made it easier to let her know it was okay. But I still have times where I need to step back and move us further away.
I also find when she is up to eating food, scattering it around us encouraged her to move and relax a little. Imitation exploring.
Yes there is so much to learn and so many ways! It can be intimidating. One thing I've been trying to do is only focussing on "the next step" instead of worrying about the entire journey to get where we want. We are still a ways off (makes my tummy do flips thinking how far to go, and how far we have come!) and sometimes there are set backs but each time is a little better as we get new habits. My current mental goal is for her to sit quietly while strangers (men) walk past. Getting there!
I do hope you try positive k9 training, for the purely selfish reason that they have been working so well for me so I want everyone to be as helped as much as me XD and we can wave at each other from a huge distance
(I am really enjoying the social aspect too. Nice bunch of people. Not something I specifically was looking for but turns out the social support here on the reactive thread and from the people at my training school have been invaluable. Especially after set backs :) )
Do you know LAT? I don't know the specifics of it but I've been doing a version of it I think - everytime my dog looks at something that scares her (that is far enough away she is only looking not freaked out) - I give a treat. The basic idea I think is that they learn to look at the scary thing (and nothing bad happens) and eventually associate it with positive/good things. This worked better for me with dogs than with people, even now I keep treats at my door incase of guests.
This is why dog classes are good I think, because you can look at other dogs in a controlled environment and know trainers can step in if you're too overwhelmed (cause we can get overwhelmed too :) )
Your dog sounds a lot like our dog, but it seems like you have made real progress! Hopefully we can too. We will definitely check out positive K9- I had a bit of a read up about them today and they sound really good, they're not too far for us to get to either. I hope all goes well with the rest of your training!