Lay out the egg roll wrappers one at a time. Place one piece of string cheese in the center near the edge, then arrange some pepperoni, sliced mushrooms and garlic around the cheese. Roll up the string cheese a little, fold in the sides, then continue to roll up, and seal the edge by moistening with water. Repeat with remaining wrappers, cheese and fillings.
Heat oil in a large heavy skillet, or deep fryer to 365 degrees F (185 degrees C). Fry enough to fit loosely in the pan, turning once after about 5 minutes. Continue to fry for 3 to 5 more minutes or until golden brown. Drain on paper towels.
Warm the marinara sauce in a serving bowl in the microwave. Serve Pizza Stix on a platter with the bowl of sauce for dipping.