The United States did its annual child soldier assessment abroad, imposing sanctions on Syria, Sudan, Myanmar, the Central African Republic and Rwanda. Only Rwanda was actually receiving significant aid in the first place, though CAR also was before the recent regime change.
The list of nations where child soldiers are used is a lot longer than that, of course, but the Obama Administration has issued waivers for the rest, including 100% blanket waivers to Yemen, Chad and South Sudan, and partial waivers to Somalia and the Democratic Republic of Congo.
The Child Soldiers Prevention Act of 2008 (CPSA) forbids the US from providing military aid to governments or militias that recruit and use child soldiers, but allows the president to override the ban in special cases on “national security” grounds.
Since the law came into effect, President Obama has regularly taken advantage of that waiver to keep the aid flowing to some of the worst human rights violators in the world.