I recommend trying Macrium Reflect - its recommend and used here extensively.
Download this WinPE ISO
, unzip it, and write it to a CD/DVD or separate USB thumb-drive. Use it to create the image to the 32GB USB you purchased for your son.
This WinPE cannot reside on the same 32GB thumb drive which will hold the Macrium image.
Read this for more info on Macrium: Imaging with free Macrium