During this Covid-19 period I was forced to use online education with my students so I increased the use of simulation tools, especially online simulation tools. These are very useful for me during this time, although they are not important and effective like a real laboratory at school, which I prefer, but only a temporary remedy. 
In these days I'm using Tinkercad  that is free program to online 3D modeling and Electonics circuits that runs in a web browser, known for its simplicity and ease of use. It is very useful for teachers who want to create a class with their students and is easily combined with Google Classroom. 

This is an example of an exercise by a student of mine: https://www.filipposfactory.com/index.php/8-arduino/35-counter-0-9-with-7-segments-display-and-arduino-uno