The pawing and digging your kitten is doing is an amazing exhibit of instinctive behavior (in that he probably didn't learn it from mom-cat). In the wild, cats often bury their food remains (as well as their feces) as a protective measure so their enemies can't track them. Conversely, they also spray their territory with urine as a warning to other predators to stay away.
Your little kitty is demonstrating this wonderful instinct, and it's a very positive sign that he is making your home *his*. Be sure to have him neutered at an appropriate age, so he doesn't follow through with urine marking.