Here are 3 simple tiling puzzles. A 5x5 square is tiled with 5 pieces, one a single sub square, the other 4 each made of 6 sub squares. The single piece has been omitted so the tiled square has a missing piece.

The four pieces of puzzle 1 are all the same. It can only be solved if the missing square is at the center. Not hard, it has a pleasing four fold symmetry.

Puzzle 2 has 4 different pieces. It can only be solved if the missing piece is at the center and is a bit harder.

Puzzle 3 also has four different pieces. It has multiple solutions; the missing piece can be a corner one, at the middle of an edge, one position diagonally moved in from a corner, or at the center. It can take a few minutes to find all four solutions.

OpenSCAD construction and viewing programs are included.