"I am prepared under my constitutional duty to recommend the measures that a stricken Nation in the midst of a stricken world may require. These measures, or such other measures as the Congress may build out of its experience and wisdom, I shall seek, within my constitutional authority, to bring to speedy adoption."
So, a possessive noun is usually used to indicate who or what has something, like "The Dogs' ball." To change this form of children,plural, to a possessive noun, you will want to add an apostrophe, and then an s. It changes to this:
