Pitching ideas to stakeholders/leadership - suggestions or advice?

I usually go with a good, better, best approach.  Go in with three levels of you idea, make the good level what you actually want, the better needs to have a few extras thrown in that would be nice, shoot for the moon on the best.  I find that most of the time you will end up with the good or better options and the leaders still think they are getting a good deal.  Every once in a while you get to shoot for the moon.  

In my case I am a contractor. I have many students and sometimes the curriculum offered by the school is incorrect，（usually misspelled). It is essential that students in a learning community are exposed to new vocabulary. Not only does this help them to better understand the concepts they are learning, but it also allows them to communicate more effectively with their peers.

When pitching a new project or idea to stakeholders or leaders, I emphasize how learning about new vocabulary will benefit students. I will explain how students will be able to engage with the material more easily and if they have a correct shared language. I use specific examples to illustrate my point and am prepared to answer any questions that may arise. By taking the time to effectively communicate the benefits of my project, I increase the chances of gaining support for my initiative. I must demonstrate why the changes need to be implemented

All the ideas that are offered by me to the administration must be innovative, creative, and factual. It takes about one month for anything to change.

I've never been an 'idea' person. The proof is in the pudding.  Years ago, I worked with an 'idea guy'.  He's started and sold several companies since that time.  We were a great team.  He was the idea guy and I was the closer.  He'd make the pitch and I'd provide the details/data.  A really nice collaboration, working off each other's strengths.  Whether pitching an idea or reviewing a pitch, there's got to be some meat on the bone.  An idea is interesting, but without thorough research and data, I'm out.  Show me the money!

If someone is pitching an idea to me, I like to see that they have done their research on the idea ahead of time, and have a good plan to implement the idea

Often they're cut-the-crap business people who want to know how your idea will benefit them and at what cost. They only are interested in the details to give them a better picture of the costs and benefits.

As the business owner, I am thankful when employees pitch ideas to me.  I think it's important to consider that leaders have many reasons why they are doing something one way and will need time and patient from an employee that thinks a different way is better.  I would estimate that about 75% of the ideas pitched to me are from people that don't see the whole picture, and their idea wouldn't work, but it is still helpful to hear a concern, complaint, or idea for improvement.  For the 25% of the time the idea would work, sometimes I don't fully see how the new idea would work well at first, but over time, I begin to understand.   So I would recommend patience for the employee and humility for the leader.

I have presented ideas many times to leadership.  My suggestions for getting this right are:

Over-prepare - do your research, know the process, implications, estimated potential cost savings, how it will better the company in tangible ways.  Have it organized and presented so that it builds a story.  Have your savings or morale increasing plans detailed and tangible.

AND - the more you know your leadership, the better you can anticipate their questions.  Always take time to consider what they might ask and craft responses.  Having a ready response could get the pitch over the finish line.

As a C-suite executive, I welcome pitches from all angles. If you have something to share, share it. If you want me to know about something your doing and would like me to be involved or support it, let me know. It is just that simple. I think the most important part of pitching is knowing who you are talking to and what it is that they are interested in. If you have strong understanding of the background of the decision maker sitting in from of you, you have a much better chance of connecting to them.

The most important part of pitching leadership, is knowing there perspective and the goal they have in mind. If you are solving one of their problems, meeting one of their needs, or innovating to create profit for their interests, then you have greatly increased your "yes" answer reply to your pitch request. If you do this successfully, positive momentum also builds, via credibility, with future requests, so this is well worth the time and effort to accomplish with your best efforts. Also, consider framing it within the organizations interests, versus your own idea. Ownership is clear, so humility is advised in this attempt.

For me, it's putting emphasis on the need for the idea or project. If I start going into the techy details, eyes start glazing over fast.
The KISS principle often pays dividends when it comes to techy projects.
I try to focus on: Why do we need this thing? How will it benefit the organization? What will it cost? How do we measure the outcomes?