Thank you so much for your replies!!

He took the EXPLORE in 5th grade (this past year). He should technically be in 4th grade because of the different cut off here in Illinois vs Virginia. He will be entering 6th grade this year. I totally agree that I would like to give him time to mature and grow and become the 'academic machine' that he'll need to be : ) But when I read Articles like "What Kids Don't Learn" I get really nervous because that is HIM to a tee! No studying, no responsibilities...he does his HW quickly and without making a fuss but it doesn't take him that long.

His area of difficulty is writing. He can talk your ear off about anything but has trouble putting it on paper and in general doesn't like to write due to weak motor skills.
Because of this, difficult to make a portfolio that fully reflects him- but it's worth a try. I will look at that thread as well.