It was very easy to make these motor planning ring stacks. I stuffed an oatmeal container with a bottle of water and fabric scraps. One can use anything, sand, gravel etc. just so that the container is full . Then when you poke the straw through the lid it will press against something and not need to go down. Next, decorate with contact paper and secure with duct tape.
I cut the little circles out of detergent bottles and punched holes in the center.
The lady in the top photo is completely blind and I like how she had to pay close attention to feel as she moved the rings downward. I originally gave her the container with 2 straws but then decided since she is blind I would make one for her with only one straw.
The lady in lower photo and video is using the single straw ring stack and I realized that she would have enjoyed some color matching. So you can adapt this to meet your client's needs....so that they can color matching as part of the process of motor planning the movements of circles downward.
I think that this can function somewhat as a fidget tool. The straw feels nice and smooth as one moves the pieces upward or downward....