Using some additional software you can mirror your iPad to your school computer then connect that computer to your projector for the whole class to see. This works for both WinOS and MacOS computers.
Here is the user guide: https://www.5kplayer.com/airplay/how-to-use-screen-mirroring-iphone-ipad-mac-pc.htm
If you don't already have the 5K Player software installed, but you'd like to do that at WISS, just send an IT Support request to techsupport@wiss.cn asking for the ability to mirror your iPad to your school computer and/or projector and we will come to help you.