What is the difference between an Experimental Design, Experimental Method and a...

[lizway]

...Research Design (psychology)? i dont know the difference! one text says one thing and another says something else. I'm confused!!

for instance,

1. a researcher conducts a study to find if babies who cry alot and get picked up immediately turn out to be spoilt children. what is the experimenter's research design?

2. uni students are asked to use a GPS to find and point towards the accurate direction of 3 locations from the lab for a cognitive mapping study. what is the experimental design? what is the experimental method?

3. three groups of lil kids are assigned randomly and told to do a puzzle and if they finish, they can all get a dollar now or 3 dollars tomorrow for the first group, 3 dollars in 2 days for the second group and 3 dollars in 4 days for the 3rd group. the researchers are testing delayed gratification. what is the experimental design?

i thought that the experimental design is just the way in which the kids were assigned, which is by random assignment. is this right?