It was easy enough for my 10 and 12 year old's to complete. Really straight forward, just need some basic resistor information, and you have to watch the orientation of the caps and diode's. Instructions were really clear. My son went on to build several other items afterwards.
I would recommend a good solder station though, cheap tool = bad result. Mine cost about $100, Hakko FX888 ESD-Safe Soldering Station
I have the build manual in pdf, I forward it to you.