Instead of wirelessly projecting your mobile device, use Chrome Remote Desktop to control your computer
Source: Chrome Remote Desktop
Hat tip to Lance Yoder over at Edgaged.net for this tip. In his district, instead of trying to wirelessly display a mobile teacher device, he flipped it. Instead, the teacher uses Chrome Remote Desktop to control a PC hooked up to the TV. This set up bypasses most of the issues with wireless, since any hiccups only affect the teacher control and does not bother the image or video being displayed to the students.
He put together a video on setting up Chrome Remote Desktop.
The video is out of date for a couple of items. Google has streamlined the process of setting up Chrome Remote Desktop. On the host machine, that is, the one connected to the projector or TV, you visit https://remotedesktop.google.com. Once you have set up the host, to control it, you will visit the same address on your mobile device.
Chrome Remote Desktop as a remote works on any OS that has Chrome, including Chromebooks, iOS devices, and Android. You cannot control a Chromebook even though you can use the Chromebook for remote.