I'm just reading this book called Big Baffling Behaviours by Robyn Gobbel which I am finding vv helpful.
I think The Explosive Child is also good but it has to come at the right time IME.
Where are you now in your parenting journey, and how much do you know about ADHD? Bearing in mind my eldest is a teenager, though I do also have a 6yo - I think I went like this:
- Believed reward, punishment and reasoning were the only tools in behaviour management. Was aware of more positive/calmer type versions of these (ie, not smacking/threatening/shouting!)
- Learnt about "behaviour is communication" type theory - that behaviour is not always just behaviour, it can be a sign of stress or difficulty. And that you can often improve behaviour by connecting with children.
- Found some "ground up" type parenting methods rather than "top down" (e.g. skill building, modelling, emotion coaching, meeting child where they are and see where they want to go, rather than expecting them to direct them where I think they should go) - liked this a lot.
- Some of these "ground up" approaches were helpful but some I struggled with. Behaviour became more intense and difficult to manage (due to age and physical size not parenting method).
- Learnt about stress behaviour - this is sort of like "behaviour is communication" but up several notches! The idea being that if your child has plenty of stress behaviour, they are likely struggling with underlying stress which can be addressed to alleviate the behaviour.
- Learnt about ADHD and how it can affect organisation and impulse control.
- Learnt about regulation and the arousal of the nervous system. This was the missing piece for me. Finally the behaviour made sense. However I was still struggling with what to actually do about it, in the moment.
- Learnt a bit about sensory processing, especially all the different movement types - a lot of this is helpful, but I still find it really difficult to find concrete info because a lot of the time the answer seems to be "it depends on the child" but without a qualification in the subject it seems really unclear to work out how to find out by observing the child!
- Learnt a bit about other types of stress and how these can be managed.
- Am now learning about the different stages of arousal, how to identify and how to respond at different stages. This is much more practical and helpful.
The Explosive Child really explains the behaviour as communication thing and gives tools for how to meet child where they are and work out what it is they are struggling with exactly, one expectation (unsolved problem) at a time. I think this can be excellent for working out accommodations, but is difficult to implement unless either things are going well enough that you can have a conversation with your child about something behaviour related without it all kicking off, OR, when you are in total crisis and you're ready to undo absolutely everything and start from 0. It can be hard to get your head around if you are somewhere in between these two points (IME). It doesn't tell you what to do in the moment, and it doesn't globally reduce stress unless you embrace the "Plan C everything" mindset (which means drop all expectations they are struggling with entirely, then pick one to work on at a time). - This may feel too extreme unless you're already in burnout.
Big Baffling Behaviours comes in at the point where you know they are dysregulated/not in control, and you are already trying to reduce stress in general but you still need a plan for how to react NOW in the moment, when things are kicking off.
Self-Reg by Stuart Shanker and anything about sensory processing or low-demand parenting should help reduce overall stress level in the background.
If you want to understand more about sensory needs or connection seeking etc The Occuplaytional Therapist tends to be good at this.
If you're less sure about what ADHD actually is and how/why it affects behaviour and what that means for parenting (rather than just the surface-level symptom observation) Russell Barkley's youtube channel is great and he has written a book called the 12 principles of raising an ADHD child which is probably good (I haven't read it). ADHD Dude can also be good (though I disagree with some of his opinions) and Seth Perler explains executive functioning brilliantly.
Smart But Scattered (book) is also helpful in terms of assessing their executive functioning in different areas, and finding areas to focus on for skill building.
There is a book by Peter Hill which MNers speak highly of, about medication. Even if you are nowhere near considering medication, I would recommend starting to read about ADHD medication ASAP. The story we tell in this country about ADHD medication is very, very skewed and it is highly likely that you currently have some ideas about it which are incorrect (I absolutely did). It sounds like you do legitimately have more urgent concerns but maybe when things are feeling calmer, it's worth looking into not because you should get him on medication ASAP, more because it's helpful to understand how the medication works and what it does so that you're clear about when and in what situations it may be helpful.
If you are trying to use reward/punishment type strategies but are finding they are ineffective or you're getting too frustrated you might look at a parent training resource like The ABCs of Everyday Parenting (free on Coursera) - this may be fairly similar to the parenting course you are signed up for already, but could be a useful supplemental resource.
Most effective things for ADHD management in children are parental education (psychoeducation) - understand what they are doing and why, what is happening in the brain, what is different to NT children. Understanding helps you be more patient and empathetic, and not tell stories to yourselves about what they are doing (e.g. he's jealous of his sister, that's why he has to ruin everything) which can be highly destructive.
Then medication (of course this is not a must, but it is highly effective, so worth learning as much as you can about it well before it comes up as a decision to be considered, rather than waiting until you feel you need it.)
Parent training in terms of how to be calm but firm, and consistent and structured when responding to behaviour you don't like. Also, clear communication and liason between parents and other supervisory adults e.g. school teacher, club leader etc.
Lastly environmental accommodations, which means things like - if your child needs a lot of movement, and tends to jump all over other people or climb on the furniture which breaks it, try to find/arrange some areas in or near your home where they can let off steam, without breaking things or disturbing others. Also consider movement breaks, wobble cushion etc for school if focus is helped by movement.
If they struggle with breaking down large tasks like "tidy your room" or "write a story about XYZ", try giving them the same instruction as a list or step by step e.g. "First pick up all the clothes and put them in the laundry basket".
It might also mean things like closer supervision or more restricted access to things like gaming than other children their age might have. Tricky to balance this one with meeting their needs while not making them feel infantilised.