Hi Dave,
As the original author of the post that Dan has referenced, I can say that Go does indeed make IMHO a good first programming language. It all comes down to how you explain things. Thanks Dan for the reference :)
I'm not going to repeat what the original discussion said, but let me try to pick out a few things.
I was teaching the very young - 10 & 11 year olds. So I had to simplify things down quite a bit. So I didn't cover things like:
* functions - arguments vs parameters I thought this was just too to big a step. Yes they used functions, but they didn't write them, including functions with no parameters and no return values.
* structs - again its just to big a jump. You can do a lot with just numbers and strings
* Local vs global variables - again too big a jump and doesn't make sense without functions.
* Anything you might think of as advanced - so concurrency, testing, packages and modules, file and network IO, even errors etc I left out.
With an older group I'd put all of those back in except concurrency, starting with functions, then packages, then IO.
But that still leaves the key things that all programming languages have in common namely variables, instruction sequencing, selection and repetition. In the UK this is what they have to cover at this age group. This is also the order I introduce these in, and over about 15 hours. So I let them work slowly. At least at this age group typing is still an issue, so they need time just for that.
Static typing I did not find to be a problem at all. The way I approached it was simple. Kids already have a good grasp of numbers (whole and fractions and decimals fractions) and words at this age. So they know that writing "hello+world" in English makes no sense. The "+" symbol is only used with numbers. So "1+1" does make sense in a different context.
All I had to do was ask the kids did they think they needed a number or a word for a variable type? If they where reading a variable from the keyboard that they had to use in a sum, they can work out they need a number not a word. If all they wanted to do was echo the variable back - say their name - then they work out it's a word. It takes a few hours, but within 3-4 hours most of the kids have worked it out. After that its just a syntax and typing problem.
You'll find that having the types helps the kids reason about the programs. This is something I personally find very difficult with python and other typeless languages. It's very hard to reason about an old bit of code because you don't know what the valid operations or data range is of a type, which especially if it a named well helps you reason about the logic. So with kids I would say you want to be as explicit as possible. Static typing helps with this.
The way I introduced numbers was subtle, but matches what they typically see in maths at that age. So a number is an int type initially. Only when we need fractions did I introduce float64, and I only talked about those two numeric types (so no int8 or float32). And I talk about numbers not int or float64, unless I have to be specific.
Words are simply strings, that's just a new name they have to learn and associate with a sequence of characters/letters. They get this really quickly.
The other approach I took was that I gave them partially completed Go programs, where the level of completion tails off each session. So I did this for two reasons. Firstly to cover a bit of boiler plate, things like the import statements and the main() function header. I do talk about these and the partial programs also explain these in the comments but I don't expect the kids to type these lines. Secondly I want them to focus on whatever was key to that session.
The programs are heavily commented to both explain what is there already and what and where I want them to fill in the blanks.
And since the programs are incomplete they won't compile and run to begin with. So they kids have to get he correct syntax from the get go. That's just the same as in English, you have to have the correct spelling and grammar, so the kids have a similar concept at that age.
If you do this they'll absorb things like main() and import just because they will be familiar. So they'll spot it if you leave it out after a few weeks. Or be able to complete an import statement (if you tell them the package name) just by coping a previous example.
My last trick was as I kept things to keyboard IO, I had a little wrapper package that hid the complexity of the text scanner class and converting form strings to ints etc that the programs used.
So to give you an idea of what I had them doing, they where printing "Hello <you name>" after inputting their name, working out how fast the ISS goes in orbit and the orbital period and comparing that to geostationary satellites, doing ROT13 encryption (so A becomes N) (in the UK they have to learn about Caesar ciphers at this age), getting them to print hello world in non-Latin languages (again works well with a divers group) and shows how you can count characters in a string.
Hopefully that helps. I've a pile of material, slightly out of date over the past 18 months as I have been busy on other projects. I'm happy to share that more widely and bring it up to date if that's any help to you or anyone else.
Good luck
Owen