There is a wide variety of image editing and publishing tools available. Included here are many excellent free and low cost options.
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Shape Collage - Automatic Photo Collage Maker
Shape Collage is the only collage maker that: optimally arranges photos creates collages in different shapes can handle thousands of photos generates super high-resolution images (up to 200… learn more
Paint.NET
Paint.NET is a free(!) image and photo editing program for Windows PCs. While not as "feature rich" as PhotoShop, it does a great job and loads faster than… learn more
PaintShop Pro
A good alternative to Photoshop is Corel's PaintShop Pro. While not the gold standard, it provides many of the same features and can be easier for schools to… learn more
GIMP
GIMP (GNU Image Manipulation Program) is a free, cross-platform image editor available for Linux, OS X, Windows, and more. GIMP can be used by graphic designers, photographers, illustrators,… learn more
GIMP vs Photoshop
This video takes a quick look at the pros and cons of both Photoshop and GIMP. And good news! GIMP version 2.8, mentioned in the video, is now… learn more
PIXLR
Pixlr, among other things, has simple and advanced photo editors you can use right on your web browser. They also make cell phone apps and desktop versions available… learn more