Can I bring google earth terrain into sketchup models? We use sketchup to design homes and need to place them on a site.
No. Google changed their terms of service almost two years ago which makes it not possible to use their Maps or Earth terrain data and images in SketchUp.
As @DaveR mentioned, you can no longer do this. However, you can geolocate your model and export it as a KMZ file. This can be imported into Google Earth and viewed there.
If you are working in a closed loop, a school, you may be able to import all your various models, once geolocated, into one local version of Google Earth so all your students can see their work on the globe.
But I may be wrong.