Are you looking for tools to create classroom posters ? The collection below has probably what you are looking for. This is a list of some popular web tools that teachers can use with their students to create visually attractive graphics that can embed a wide range of media forms including: image, text, graphs, and drawings.
I personally find myself using Google Drawing more often than anything else. I find it much more practical as it is already integrated with Google Drive and so everything I create on it is automatically saved to my Drive account. Google Drawing also has a simple and easy to use set of drawing tools which I am pretty sure your students will enjoy working with. I have already written a detailed visual guide on how to use Google Draw to create classroom posters, I invite you to check it out here.
There are also several good alternatives to Google Draw which you can find below. This edshelf list is curated by Holly Witt and I came across it in teachthought.com.