One of my favorite toys to use is a wooden train set. Depending on the child, I use it for many reasons, in this case it’s for motor. Building the train set helps with balance and coordination. I’m not an OT/PT so I don’t know the correct terminology, but the child is in a tripod stance where she is using her arm to support her weight and keep from falling over.
While putting the train together, if the magnetic ends don’t match, she needs to use her fingers to rotate the train and make it “click” together. She also has to use both hands to line up the magnets.
The idea is to make the track long enough so that she has to move around it. The constant getting up and moving around is great practice for her muscles.