Sansuu 5 & 6 Nen - Keisan Game is an educational NES game released by Tokyo Shoseki on October 30, 1986. It helps 5th and 6th graders boost math calculation skills through interactive play, with 4 modes: decimal multiplication (side-scrolling shooter with decimal multiplication puzzles), decimal division (similar shooter with decimal division problems), fraction addition/subtraction (field-based fraction puzzles with flower mechanics), and fraction multiplication/division (similar field mode with fraction operations). Each mode has multiple difficulty levels and supports 2-player alternating play, letting players improve math skills while having fun.