For a notification-heavy app, I'm surprised at the lack of consideration given to Queue/Topic Messaging servers. 5B notifications/month isn't quite 2k/s, which really isn't all that onerous. Routing within messaging apps would seem like a natural fit.
There are positives to the data-entry pain: once somebody's entered their data, they have a real investment in your system. Question banks can be reused and grown, so the pain does decrease over time. Depending on how easy or difficult you make it to export their data, it may help user retention.
For users zero to ten, you might want to consider taking this problem off their hands: let them upload a photo of a worksheet, and let the system "magically" transform this into the proper format. (ie, OCR the data, then edit it yourself or pass it on to mechanical turk). If they're not completely convinced of your value, even with this level of assistance, then you've got no market. If they do buy in, then you can figure out how much pain you can leak back into the system before they balk.
One potential value-add: math problems from teachers often have hard-coded values. Current test-bank software lets teachers convert these to formulaic question generators, but this is even more time-intensive of a process than straight data-entry. Applying some "magic" to this process is a ripe opportunity.
How is this new? Surface plasmon resonance effects with gold are, I'd thought, an exciting but well-understood phenomenon in nanotech.
Using gold nanoparticles to achieve unique photonic effects has been done since the Roman Empire and the Lycurgus Cup (this artifact used relativistic behaviors of gold to show two different colors, depending on the light source being either reflected or refracted)
Speaking as a developer who joined a project started by a guy who had a great idea for a business, the things I looked for was a really solid business plan, a good understanding of the problem domain, and a map that showed how we could get from here to there in 18 months.
I might be more cynical than most, having gone through 3 dotcoms as a developer, but I'm also more optimistic than most (having earned less than 20k in the last year while we build this thing and I earn my pony, and the estate upon which to esconce it).
Don't sweat the code if that's not your strength: focus on your business plan. Most seasoned coders have seen umpteen
'cool ideas' burn and die, and it's usually not technical issues from which Demise doth spawn. The one freakish happenstance of the current market is that, while most coders are not great risk takers, they are wonderful risk-smellers.
Some background: the progenitor of my current gig spent the last 3 years trying to build a business. He tried to outsource, and contract, and everybody told him it couldn't be done. We met through a mutual business acquaintance, and I fairly scoured his plans. 3 months later, we had a working prototype, and we launch in 4th quarter 2007.
If you are truly God, please implement ASAP