Canva

Canva is a visual communications platform that allows you go create wonderful designs - everything from infographics, posters, presentations, social media posts and more. It is quite intuitive - drag-and-drop millions of images, illustrations, videos and text elements. If you sign up for an educator account here are over 60,000 educator-created templates that include flashcards,

Canva introduced an education plan that offers "pro" features for free at https://www.canva.com/education/

Here's a good article from Richard Byrne on using Canva in the classroom:

https://practicaledtech.com/2020/01/07/ten-things-you-can-do-with-canva-in-your-classroom/

Canva has introduced real-time collaboration options. Here's another article from Richard Byrne describing this: https://www.freetech4teachers.com/2020/07/canva-introduces-real-time.html