This 256 page paperback collects the facial expressions from babies to teens 19 years of age. They are all head shots and there are 32 on one page, that's a lot, covering many possible angles.
The expressions can be a bit exaggerated at times though. On some photos, there are some lens distortion. I suspect the camera uses a slight wide angle lens so there's some distortions typical of such a lens - fish eye effect or objects near to lens appear bigger and those far away are much smaller. Just note that the portraits are not 100% accurate in this case.
Right at the back is a small section on phonemes and the kids wearing different hats.
It's a decent reference guide but note the limitation.
If you want to learn more about facial expressions, I would recommend The Artist's Complete Guide to Facial Expression by Gary Faigin.
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