SketchUp for Schools is a free online program. SketchUp for Schools is a 3D Modeling program that has great tools to make whatever creation you'd like. There are tools like tape measure or zoom extents that are really helpful but aren't thought about commonly. The tape measure tool is basically a tape measure but it's really helpful when you don't want to have to create a line. The zoom extents tool is used for if you're zoomed in/out to where you can no longer see your creation. If the tool is pressed it will take you to your creation. Basically it zooms you in/out to the size of your drawing. Tools like these are really helpful and SketchUp provides them to students to learn how to use softwares like and more advanced than the program. SketchUp for schools has a payed version, if you go to the actual website, (The website for Sketchup, not for schools.) You can pay money for more advanced tools that aren't in SketchUp for schools. If you don't want to pay $100+ then the free version would be a good replacement. There are also Sketchup alternatives like Archicad, AutoCAD, and lastly Revit.