Reddit reviews The Out-of-Sync Child Has Fun, Revised Edition: Activities for Kids with Sensory Processing Disorder (The Out-of-Sync Child Series)

This sounds like my son at that age, who was also middle of the spectrum. the developmental pediatrician recommended Floortime for us, which is an approach that was developed by Stanley Greenspan (child psychiatrist) together with Serena Wieder (I think psychologist). Sadly, Dr. Greenspan has passed away. However, I found those books and materials helpful, and we also received some help from trained Floortime therapists in our area.

Here is a youtube video of Dr. Greenspan helping a family: https://www.youtube.com/watch?v=vApghedypFc. That same channel has a whole bunch of videos: https://www.youtube.com/user/greenspanfloortime/videos

Here are some things you can check out in that direction, if you are interested:

1. one of his books ("engaging autism") on amazon, it has a bit of a preview you can look at: https://www.amazon.com/Engaging-Autism-Floortime-Approach-Communicate/dp/0738210943. same book on google books has a preview, not sure if it's the same preview! https://books.google.com/books?id=6MkBAwAAQBAJ&pg=PP1&lpg=PP1&dq=%22engaging+autism%22%5D%5D&source=bl&ots=Kifx6vM8fg&sig=odVVaeTq0bBI68Ak3IKNThnE3SM&hl=en&sa=X&ved=0ahUKEwjh76X-mKjWAhWBOSYKHYOsBDkQ6AEIMjAC#v=onepage&q=%22engaging%20autism%22%5D%5D&f=false
   
   
2. some materials from the florida department of health about implementing the approach: http://www.floridahealth.gov/alternatesites/cms-kids/providers/early_steps/training/documents/floor_time.pdf
   
   
3. a short 2-pager from one of the organizations that implements the approach: https://www.stanleygreenspan.com/swf/The%20DIR%20Floortime%20Model.pdf
   
   In addition, this book here changed my life in terms of altering my outlook and helping me think more positively -- the authors are parents and doctors, and the mom-doctor is a neurologist, in fact -- there are some concrete helps in here -- a lot of the material is better for when your kid is older, maybe, because a lot of it is about helping them at school, but it helped me to shift my focus in a more positive direction, and just gave me a good framework for understanding things: https://www.amazon.com/Mislabeled-Child-Solutions-Childrens-Challenges/dp/1401308996/ref=sr_1_1?s=books&ie=UTF8&qid=1505513398&sr=1-1&keywords=the+mislabled+child
   
   Finally, I recommend this book, which can help you understand the sensory issues: https://www.amazon.com/Out-Sync-Child-Recognizing-Processing/dp/0399531653/ref=sr_1_1?s=books&ie=UTF8&qid=1505513523&sr=1-1&keywords=the+out+of+sync+child.
   
   And then get this one: https://www.amazon.com/Out-Sync-Child-Has-Revised/dp/0399532714/ref=pd_sim_14_1?_encoding=UTF8&psc=1&refRID=7NP2KCQY50ZRWTC9JQA0, which will help you design activities around the sensory issues.
   
   I stopped here because I didn't want to overwhelm you, but let me know if you want more recommendations, more info, or more shared experience. happy to help, just let me know. feel free to pm me also. my kid is now 10.

http://www.amazon.com/Out-Sync-Child-Carol-Kranowitz/dp/0399531653

http://www.amazon.com/Out---Sync-Child-Has-Revised/dp/0399532714/ref=sr_1_2?s=books&ie=UTF8&qid=1395696989&sr=1-2

Read these, get him into Physical and Occupational Therapy, be an active part of it and work on creating the environment that best suits your family without setting him off.

Every child is different, and there's no easy answer for SPD, but these books will get you started.