All of these games and puzzles can be played solo but also could be used along side a partner. The ages are recommended by the brands but I think that many of the 8+ have more to do with reading the puzzles rather than being able to participate in playing. Critical thinking skills, deductive reasoning and logic are some of the skills that are mixed in these fun and challenging solo player games for kids (and adults too)!
Geobrix // Ages 8 + // 3-in-1 challenge puzzle
Tangoes // Ages 5 + // This classic game includes different shaped puzzle pieces that you have to use to create different puzzle challenges including animals and objects
Swish // Ages 8 + // This game uses transparent cards with different dot patterns, the goal is to determine which cards are needed to solve each puzzle when the cards are stacked on one another
Gravity Maze // Ages 8 + // Use logic and STEM skills to solve these marble run 3-D challenges
Kanoodle // Ages 8 + // 3 different 2-D & 3-D puzzle games in a travel case
Izzi // Ages 8 + // Use critical thinking skills and black and white tile pieces in this game to solve different visual puzzles
24 // Ages 9 + // This game uses all four operations (addition, subtraction, multiplication and division) to come up with different combinations of 24. You start with 4 different digits and have to use all 4 to somehow get to 24. Great for not only fact practice but also for trial and error and flexible thinking. For next level challenge it also comes in double digit, integer and fraction/decimal.
Rush Hour // Ages 8 + // Use logic and problem solving strategies to get the red car out of rush hour!
Logic Links // Ages 6 + // Use deductive reasoning skills and trial and error to solve these increasingly challenging logic puzzles
On The Dot // Ages 10 + // Use spatial reasoning skills to stack these transparent cards on top of one another to solve
Logic Dots // Ages 8 + // Deductive reasoning and spatial planning skills are used to solve these logic puzzles