I love your idea of having students write a formal persuasive piece with the prompt being a "funding request". I am a grand advocate of meaningful and effective teaching that students will be able to use in the future. There are many ways and ideas on the funding request! This could teach students how to write formally and the kind of language/tone that they should use or avoid in their writing. It also shows students how subjects are constantly integrated within one another. Concluding my thoughts, it truly shows the power of writing and how purposeful it is.