Child products should NOT show in product searches

[fatcreat]

My client has a product with options small and large.  Each of those options has a different weight, length, width and height. After an order is placed, I need to create a csv downloadable file orders file and include the weight, length,width, and height. That file is then uploaded to Fed Ex shipping. I think I need to set up my products with a parent/child relationship so you can choose small or large on the front end and then small and large products each has a length, width, height associated with it.  However, what I don't want is the child products to show up on a product search.  Only the parent products should show up on a search. I tried to unpublish the child products, but then they do not show in the front end, which makes sense.

Is it possible to do this?  Other than parent/child, I'm not sure how else to store and then later retrieve the weight and dimensions.

Thanks for any suggestions!