How to backsave SketchUp 2020 file to SketchUp 2015?

I have to do a school project. The school computer’s all run sketchup 2015, but from our subscription, we can install the latest sketchup at home. How can I use 2020 sketchup and export to 2015?

File>Save as. Select SketchUp 2015 in the dropdown.
Screenshot - 2_11_2020 , 4_38_33 PM

Thanks, I failed to notice that! Can we do this on sketchup web as well?

No. Not that far back.

Since you are already using 2020, you could download the file from the Web version to your computer, open it in 2020 and save back to SU2015.

If it’s entirely for non commercial use, one option would be to install Make 2017 and use that to convert the web downloads into 2015. The web download can do 2017.

https://www.sketchup.com/download/all

You could use the Eneroth Legacy Save extension with your copy of 2020.