Here are a few FREE online resources that may be helpful during your tutoring session:
Subject: Science, History, Technology
Subject: Games for Spelling, Math, Strategy, Skill
Subject: Math Games(K-8). If you need work a specific skill, this website probably has it!
Subject: Math Games
Subject: Math Tests
Subject: Online Reading
Subject: Biology Games
Subject: Variety of Educational Games Including Sports, Music, TV, etc.