I would like $protected $foo to be assigned 'foo' in the static::creating event, but when I output the final object, the property is null. The event does not seem to fire:
namespace App;
use Illuminate\Database\Eloquent\Model;
class Item extends Model {
    protected $foo;
    public static function boot() {
        parent::boot();
        static::creating(function (Item $item) {
            echo "successfully fired";   //this does not get echoed
            $item->foo = 'foo';
        });
    }
}
What am I doing wrong?
Your code is working fine, I tested at my end in this way
In Model
protected $foo;
public static function boot() {
    parent::boot();
    //while creating/inserting item into db  
    static::creating(function (AccountCreation $item) {
        echo "successfully fired";   
        $item->foo = 'fooasdfasdfad'; //assigning value
    });
    //once created/inserted successfully this method fired, so I tested foo 
    static::created(function (AccountCreation $item) {
        echo "<br /> {$item->foo} ===== <br /> successfully fired created";   
    });
}
in Controller
AccountCreation::create(['by'=>'as','to'=>'fff','hash'=>'aasss']);
in browser, got this response
successfully fired
fooasdfasdfad =====
successfully fired created
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