Tangrams are among the most versatile of puzzles.
The 7 piece square is a very old design and was extremely popular around the world for the first half of the 19th century, mostly with adults though the appeal is now to both adults and kids. It is a common item in schools. Tangrams will make many many shapes beyond the square. 2 included instruction sheets provide 72 different shapes that you can make, each of which requires all 7 pieces. Google "tangram patterns" to see hundreds more.