Handedness
Handedness is which hand you use most often for tasks like writing, throwing, or eating.
Most people set their fork on the left side of the plate and their knife on the right. That fixed side matches their stronger hand. The fork and knife do not switch — one tool stays in one spot. Handedness is that same built-in preference for one side over the other.
Explaining handedness by grade level
Most people pick one hand that feels best for writing. Try writing your name with each hand. One side feels easy and the other feels clumsy. Your brain likes one hand more, and that is your handedness.
Projects that explore handedness
Most tasks use one hand more than the other, but mirror writing makes that gap especially visible. Every letter is reversed so the text reads correctly only when held up to a mirror. When 10 left-handed and 10 right-handed participants write the same short phrase this way, comparing their average times shows whether one group finishes the challenge faster and with better accuracy.
Most people are right-handed, so left-handers make up only a small share of any group. To measure how small, students in six classrooms of 12-year-olds each write their name in a registration book while an observer records which hand they use. Students who can write with either hand are counted as right-handed. Across all six classes, the left-handed total comes to just 6.3 percent.
Which hand you rely on for tasks like cutting or gripping is only part of the picture — the non-dominant hand still matters. Five left-handed and five right-handed participants each cut out shapes with scissors and screw nuts onto bolts, doing both tasks once with each hand. Left-handed participants score much closer to 1.0 on the ambidexterity scale, while right-handed participants score around 0.55. That means their non-dominant hand is considerably slower by comparison.