Brad Vaughan designed a set of tetromino blocks and trays, including a larger kid friendly set. (Get them addicted to Tetris-objects early!) But as he warns: “No guarantees on that though. Kids will be kids.”
Obviously what this world needs is MORE tetromino designs. This includes 2 different sizes, including a [potentially] baby safe 40mm version…. There’s even a holder for the smaller 10mm design that holds a ‘complete set’ of 2 of each design.
Below are the images he used to plan the two trays — two of the tiling solutions for the pattern of shapes. From Wikipedia.org: