I am running a little business in Germany targeting teachers and schools. We offer fun and sporty adventures for school trips and other extracurricular activities. What we do is "new" so nobody is typing our services into google (example: Tablet Touren - it's a fun new interactive version of a scavenger hunt).
There are no common words for when a teacher is looking for what he should do with his class on their next fieldtrip.
I figured "school fieldtrip organizers" as the first keyword after seeing your description, and then you can prefix or suffix this phrase with your location/ specific area like "School trip organizers hannover" and so on.
You must be having atleast 1 competitor in your country or in the world (I found many after searching for the above keyword) and then you can see which keywords are they targeting by either checking their source meta or using google keyword planner.
I got many combinations already by doing so (in 1 minute) like:-
1. School trip agents
2. ideas for school field trips
3. school fieldtrip ideas nearby
4. School fun activities organizer
5. School field trip experience
and then so on, and since your business looks highly location specific then do consider adding location name in your targeted keywords.
I can help you more should you ask for, with all this info.
Secondly, all these SEO tactics are for inbound lead generation and I'd suggest you to do consider outbound tactics at the same time since it is relatively new business offering and reaching out to your customers proactively instead of waiting for them to come on site is more important and i believe you know this, I'm just emphasizing.
For my business of App development (https://www.agicent.com/blog/top-10-mobile-app-development-companies-india), I rely on more human-like keyphrases through instead of what google planner might suggest, it is good to measure the volume of search though.
So a combination of tactics and tools would work, instead of just one way.
Identify who your closest online competitors are, and forget about potential brick and mortar and bigger competing businesses offline.
Don't just look for other website that offer your products and services but instead go wider to find sites where your target persona/audience is likely to be hanging out and spending their time.
Gather 4-5 of these URL's and drop them into SEMRush, use the SE Keyword reports to find the sites with the largest overall footprints and export those lists of terms. Keep this all in an Excel file for now.
You'll then want to build some simple filters to separate and tag the terms that are commercial/show buying intent, and have search volume. The average CPC numbers (the price someone is willing to pay, on average, for Ad clicks from Google is a good leading indicator on the commercial value of the keyword -- but it's only really applicable for paid search.
To get organic search competitiveness dialed in you'll need to enrich this data with additional metrics like links and topic relevance, for which you'll likely want to use Ahrefs or Majestic.
For a much more detailed explanation of the process from soup to nuts check out:
I tend to do this with businesses.
I find a set of keywords, where I guess the niche has money + very little access.
The register a domain which relates + is catchy + easy to remember.
Then I completely ignore SEO + searches, because there are none. This means zero competition + using offline marketing.
I do offline marketing by speaking to groups my target niche/audience attends.
Then continually drop the domain name during my talks.
When I say drop the domain name, I mean the domain name as a phrase, not the actual domain name... so...
Find use a domain name which is a phrase you can mention repeatedly to gain mind share traction in people's minds.
Then speak at related Meetup + conferences + networking group events.
After a very short time, you'll start getting exact match searches for the domain name (phrase) you drop in your talks.
This may seem like a lot of work.
And, to me building $1M dollar businesses this way has worked every time. Other approaches I've taken have never produced the same large effect, as speaking to groups.
Side note: Keep in mind. When you speak to a group. If you wow your audience, they tell other people in their niche. So you may speak to a group of 30 + reach 1000s over time.
This means, to me, I speak with anyone who asks. No group is to small, because who the people in the room know, is anyone's guess.
The best way to optimize is to combine the words for your new services with the commonly used words people use to search for services in your field on google. For example you can use Tablet Touren Fieldtrips, Shool Trips with Tablet Touren, Tablet Touren Adventures, Tablet Touren Student Teacher Sevices etc. While optimizing your web content you should do research keeping in mind your target audience and should then choose combination of right words without going sloppy. Also keep in mind that search engines do not like lots of the same word appearing over and over again and you will get penalised for it, it will also make your content appear poor putting off any visitors clicking on your site but it does not mean that you should use your keywords only once but you should use it sensibly primarily keeping you services and audience in front of you.