As America celebrates its 250th birthday on July 4, the Forward celebrates the 166th birthday of its founder and first editor, Abraham Cahan on July 7. The socialist newspaperman founded the Yiddish-language newspaper known then as Forverts in 1897 to help Jewish immigrants navigate life in their new home. To celebrate, we’re highlighting letters to the editor from fifth graders at Guggenheim Elementary, a public school in Port Washington, New Y…