Tens of children referred to the Institute for Halakha and Technology asking whether they couid play with the "spinner", a small spinning three-leaved circular toy which has become a worldwide hit with children.
After the rabbis dismantled the spinner, they ruled that the regular type can be used on Shabbat, but the glowing type is forbidden because the spinning causes an LED bulb to light up.
However the rabbis of the institute recommended that children not bring the spinner to the synagogue on Shabbat and not play with it during prayers and during the reading of the Torah.