How to make score more bigger? I need write some exercise to my students.

the main thing is the space size in page settings, almost everything else scales with that

besides the view or magnifying button next to the arrows under the word "style" , there is another way...if you left click on the clef, click on "staff Properties" from the menu. Go to the upper left corner of the box that pops up, and you'll see the word " Scale: "right above the bolded words "part properties" above the line thingie or divider in the box... The fill in box should say 100.0% with arrows after it...To make the score bigger or notes bigger, type in 150% or 125% for the scale number in that box.... click ok...the clefs will become bigger for you..

I find in my experience with this "200%" often tends to be a little bit too squishy for my taste but then again, I guess you could work that out either going to the staff properties box like you did before, and for the box above the scale box, increase the number 0.00 sp to a higher number if the clefs are too close together...or you can actually make the number negative to compact the clefs in order to be able to see the everything at a higher magnification level in the page view... the page layout option is also another way to "tweak" the page settings which may be able to make the notes or clefs bigger as well depending on how you alter the page length vertically or horizontally as well as the margin space amount for the sides and bottom of odd and even pages... hope that helps

What was not clearly explained was that you need to increase the scaling in the menu Layout->Page settings. As you increase this number, the preview will give you an idea of how it looks.