Photo/video editing & design/publishing software
Fotor is a photo editing tool which requires no downloads. It also provides templates for collages, for banners for social media sites, blogs or websites.           
Pixlr is another browser photo editor for which no downloads are needed. With Pixlr O-matic you can transform your photos into vintage images by adding retro effects, overlays and borders.   
Animoto is an easy-to-use tool for creating videos and slideshows. Educators can apply for a free Animoto Plus account for use in the classroom. Its features can be used to create presentations incorporating images, video clips, music and text.
Thinglink is a tool for creating interactive images and videos. You can make your images come alive with video, text, images, music and more. It is possible to upload, tag, share and manage your interactive images across different platforms. There is a free “Basic Edu” plan for teachers which allows you to test interactive images in education. Students can have individual accounts without requiring email.
Windows Movie Maker is a free software for creating and editing videos as well as for publishing them on the web/social media sites. You can also make movies out of photos and edit and add a soundtrack to your video.
Scribus is a free desktop publishing software that helps you create great looking documents of all kinds, such as flyers, posters and school magazines. It comes with a lot of support options to help you achieve the best results. There is a community around Scribus that assists beginners and professionals alike, e.g. through a mailing list and wiki.