Acorns aren't really thought of as food by many people these days, but cultures across the world have used them as a food staple. They can be eaten raw or roasted but blanching the removes tannins that cause the acorn to taste bitter.
To use acorns to make flour or to eat roasted you have to first shell them. Then warm them in the oven to kill any worms or larvae you might have missed on a visual inspection. Then chop the acorns and pour hot boiling water on top of them and let them sit for awhile, drain the water and repeat this step until the water stops turning brown. After that you can strain off the water and dry the acorns in the oven. The acorn flour is gluten-free.
Acorns have amazing nutritional value and are abundant in many parts of the world. Different oak trees have different amounts of tannins in them so some require little blanching and may even be eaten raw and roasted others are very bitter without first blanching. As you can see mine aren't ripe yet but this fall and winter I want to use some in some recipes.
Our house is surrounded by huge oak trees I believe they are white oak but I am not quite positive. Acorns can be used to make pancakes or flat breads but acorn flour will not rise on its own. They can also be used in stews. Make sure you positively identify any wild edibles before consuming them and do not eat anything where chemicals/insecticides have been sprayed.
I haven't tried any of the acorns yet because they aren't ripe but my dog Ruby doesn't mind. She loves to eat acorns and is no worse for wear. Animals love them and an abundance of acorns can signal a good place to hunt or trap animals for food also. Be safe and enjoy all that nature has to offer. Keep an eye out for my upcoming posts on wild edibles and look for a contest that my wife 
will be starting involving wild edibles.
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