All three of them appear to be US Army insignia from the 20th-century. The large one appears to be a hat insignia. The two smaller ones are collar-disc insignia. Close-up photos of their backs are needed to give you precise ID and dates for each of them.
Thank you for the photos of the discs' backs. The photos show the emblem on the discs is "applied" to a blank disc, which means your US Army collar-insignia discs date from 1937 to 1943, and in some cases, through 1945. Your hat-insignia disc is apparently from the same time-period.
The "style" of your collar-disc insignia is called a Type 3 disc by collectors. The Type 3 disc is distinguished from other types by having an ""applied" emble, and threaded-post for attachment to the uniform's cloth, and the post is encircled by a thin disc with two pointed prongs. You can learn about the various types of US Army collar-insignia discs (including dozens of photos) here: Dating Metallic Insignia: Collar Disks
As mentioned above, your discs definitely date from the World War 2 era. Your collar disc with the castle is a US Army Engineer Battalion Headquarters insignia. The one with simply the letters U.S. and a number represents the US Army's 118th Infantry Regiment.