Good morning, Brad and company!
You've had some really excellent advice here from Mary and Dee, to which I just want to add a couple of things.
I need to start though by saying as a British person I know virtually nothing about the CAP - I think it's what in the UK would be called "Air Cadets". So bear that in mind with everything I say.
I think you have come across a fab niche. There's a clear gap in the market here, and that should be your driving force. Numbers are important, of course, but as the Action Guide says, don't become number bound. You've seen a gap, and you are in a great position to plug it.
Your site concept, as I understand it, would be tightly focused on cadets and, to some extent, their parents. I had a look at the official CAP site and found it very formal, dry, and impersonal. And, to be honest, a little boring. Yours will be very different to that - you are (as I understand it) all about making this a personal, exciting and as stress-free as possible experience for young people and their families, and you're writing it from a young person's perspective which gives it your unique twist. Brill!
So, as Dee says, you're not competing with the CAP site - you're providing a site which enhances it. This is important:
Plus, you'll come at the subject from an entirely different angle (spin) ... a family who has been "thrown into the deep end" without a life ring. You and your kids will provide that life ring for other families with your "here's how we survived" info.
There's your hook
. You know the problems new cadets and their families are facing. Your aim is to make their lives easier - solve the problems for them. My guess is this would not only be in the sense of uniform, although that's obviously important. Do kids become worried about joining? Whether they'll be able to keep up? Whether they'll make friends? Do they have to go away from home, maybe for the first time? All that could be information both parents and cadets want to know, and have a place to share their own worries, too.
Again as Dee says, the keyword numbers for "Civil Air Patrol" are ok if not stunning. The keyword number for "Cadets" (and I accept this is too general because it applies to all cadets) is...
Which again is not ideal - supply is almost equivalent to demand - but your niche will be focused.
So how about combining the two and having "Civil Air Patrol Cadets" as your site concept? Which is basically what you're saying it is. And then finding a great tagline (which is the fun part): "Civil Air Patrol Cadets - everything you want to know but are afraid to ask!" - or "CAPC - the Ultimate Survival Guide" - or whatever fits.
Doing a vertical BI! search for "cadet" (singular and plural versions) comes up then with a long list of keywords. Not knowing the niche, I have no idea whether any of them are relevant but I would think some must be.
Now leave the computer alone for a while and do a brainstorm, all of you together. Think back to when you were just starting out. What did you want to know? What words would be the ones you'd put into search to get what you're looking for? Brainstorm a whole list before you go back to check them out in BI! Your keywords do not have to contain the words "Civil Air Patrol", nor "cadet/s". Think of this from your cadets' point of view, and / or from their parents' concerns.
For example, I have a site about keeping backyard chickens. Some of my keywords contain "chickens" as part but some do not. I know my audience, so I know that some people who keep chickens want to hatch. So I have an entire section (and a course!) about incubating. All the pages on that section are related to chickens but don't have "chickens" as a keyword. "Incubation", "candling", "hatching" are all keywords for me related to my subject but without the site concept keyword.
Where I add in the word "chicken/s" is on the page content itself. Because Search Engines are now very sophisticated, they read the entire page to understand what it's about. So you may have a file name just called "fitting your uniform" (for example) which could refer to any uniform. But in the page title, description and in the content itself you make it clear it is solely to do with CAP uniforms.
Is this making any sense to you at all?
The other majorly important thing I think you need to consider very early on is, where will your traffic come from? Are you going to rely completely on organic traffic via Google? That's important, but so are other sources. Social media is an obvious example. Where do CAP cadets hang out? One of the major platforms? Or forums somewhere? Or is there nowhere yet?
What support can you expect to get from the official organisation itself (ie CAP)? Would they be prepared to link to your site from theirs? Is it worth contacting them now to ask?
I had a look at Pinterest, too, which threw up some interesting ideas. If you go into Pinterest and, in the top search bar, enter "Civil Air Patrol" this is what comes up...
See the coloured tabs? They are keywords people use when searching on Pinterest for CAP. Remember that Pinterest is not really a social media platform any more - it's a very powerful Search Engine. So take a look. Click on the coloured tabs to drill down a level and see what else shows. Does this throw up other ideas for you in terms of what people are looking for? Add them to your list to check later on BI!
Click around the grey tabs underneath, too - look particularly at "People" and "Boards" and take a look at who is posting, and what they're interested in.
Having spent a bit of time there myself this morning I would say Pinterest is definitely a platform you could do well with in terms of linking back to your site.
Anyway - I don't want to overwhelm, but just wanted to give you a few more ideas to unstick you from where you are at the moment.
And one further thing: we have all been where you are now. The important thing is not to get dispirited. Keep moving forward. Keep sharing ideas.
You will be fine. I can feel it in my bones.