Place a piece of string cheese near the bottom corner of one egg roll wrapper (keep remaining wrappers covered with a damp paper towel until ready to use). Fold bottom corner over cheese. Roll up halfway; fold sides toward center over cheese. Moisten remaining corner with water; roll up tightly to seal. Repeat with remaining wrappers and cheese.
In an electric skillet, heat 1/2 in. of oil to 375°.
Fry sticks, a few at a time, for 30-60 seconds on each side or until golden brown. Drain on paper towels. Serve with marinara sauce.
You are going to have egg roll wrappers left and it's not a good idea to re-freeze so you can make something else - I sometimes make pork pasties or egg rolls, or more mozza stix if I'm having a crowd.