I'm guessing Khaki Campbell on the brown duckling.
The mixed bag photo- The duckling in the back-right corner looks upright so maybe a runner.
The magpies look great.
How do they like the aquarium?
The brown one is a Khaki Campbell. The yellow ones are hard to tell at this point, there are several breeds that look very similar to that when they are that young. Wait another week or two and post more pics, and we'll be able to help you out.