Keep trying la. I think your son just not used to have food from spoon and he doesn't know how to get food from it. My son had the similar problem when we just start feeding him rice ceral, but he was ok after about 5 days of trying. Also, when you feeding him, try to open your mouth in front of him and say "AH", then put a spoon in your mouth (not his spoon) and say "UM". He can learn from you ga.