Autism and Homeschooling

I live in the Middle East and the facilities here - for children who are anything except ‘typical’ in the neurological and physical sense - are severely lacking. My son will be 3 in July, and thankfully, he can read (definite hyperlexia), can count and knows shapes, planets etc. He loves playing and doing stuff with art supplies etc. However, as soon as he holds a pen he gets carried away then has a complete meltdown when he goes ‘out side the lines’ like uncontrollable screaming and hair pulling (mine) How is anyone managing the homeschooling? Are you getting a curriculum from somewhere? Where are you getting your resources? What are your struggles?