The slider currently used to set the quiz size for a schedule is extremely difficult to use. I wanted to change a schedule's quiz size from 20 to 40, but that was not possible to do using the slider as intended. On mobile, you can't see the quiz size as you adjust it, because the slider is entirely covered by your finger, and the smallest movement makes the number jump by a large amount; I tried to slide it very carefully, but couldn't get it to increase any less than by increments of about 30. On PC, the number on the slider is visible, but again, minor adjustments are nearly impossible, with the slider going from 39 to 43, but never 40, no matter how slowly I moved the mouse. I ended up selecting the slider with the mouse, then using the keyboard arrow keys to move it left and right; this was the only way I could get the slider to move in increments of one. It would be nice if the slider could be replaced by a text input box where a number could be typed in, like how the number of new terms is set.