Glued together

Good old fashioned Elmer's has been making fine-motor skills stick for ages. Twist the cap using both hands, turn it upside down, squeeze it tight, put the glue where it needs to go, use the right amount. Every micro-step of using glue promotes independence by developing: bilateral coordination, grading of force, sequencing of steps, tolerating sensory stimulation and visual motor control. And that's not even an exhaustive list!