I will grant you K-12 is difficult to break into. This is advice for specifically Georgia. I am not familiar with other states. Clever is a path through teachers. Teachers generally push joining Clever not Ed Boards or parents. ERate is a path through district boards. Parents don't care or understand what/how technology is being used in the classroom. They see iPad, Surface, Chromebook and generally think that most kids can access the same stuff they can on the internet. It is really locked down and usually through Lightspeed Rocket, Palo Alto, Cisco Umbrella/OpenDNS. Many push DNS through Umbrella or forcesafesearch.google.com. Make sure you accessible. Accessible also means you are categorized as "safe". "unknown" or "unsafe" will keep you out of schools.

Chrome extensions, chrome extensions, chrome extensions. I cannot stress this enough. This is the "hidden application pool" that students, teachers, and principals pull from. There is a cottage industry that does nothing but figure out extensions to create, disguise them as "informational sites/extensions" in order to give kids access to games so that they can show ads. It is a constant thorn in the side of IT.

If you have a chrome extension ...teachers will find you.

Most ERate customers make purchases on 5 year contracts or a "buy once keep forever" model...month to month is a pariah. This is due to the fact that with ERate government funds projects, software, and infrastructure can be purchased. ERate funding is viewed like the lottery.

In Georgia at least there is a state run "Tech" board (email list) where different techs exchange ideas. They make recommendations to the individual school boards. You get someone to champion you there and you will pick up several districts.

...again good luck.