My boys ages 12 and 13 jumped right in when they got their birthday gifts of the Idaho Falls, Bountiful and Salt Lake City Temples through Brick'Em Young. My 12 year old can build anything with Lego's and was challenged well while also keeping within his ability. He put the Salt Lake Temple together in about 3 hours and wanted to build more. There are 1,540 pieces to the Salt Lake Temple and he stuck with building it until completed. He rarely sits still and concentrates that long. He also stated. " This makes me think of how hard people must have had to work to build the real Temple (SLC) and now I feel more connected to them. I am going to treat the Temple with respect! Both boys loved this concept. My 13 year old is also easily distracted and he stayed focused much longer than usual. It took him most of the day to build the Bountiful Temple and I am happy to say he stayed with it and completed it. He too wanted to build more things. Instructions were accurate and easily read. Wonderful product! Excited to see what new concepts and designs that will come next. Absolutely worth the money, quality excellent, and will be buying more! Thank you Brick'Em Young for giving my children a wholesome activity and experience!