Year-long Engineering Project ideas?

In my highschool, we have four levels of engineering for each grade level. This year, the senior level, which is design and development has a total of two students (out of our ~1,000 student school), those two are me & my friend.

Last year, Design & Development had about ~12 students and they spent the year designing a new building that could be used as a new Engineering building for the school, and despite them having now graduated, they're actually still working on getting the funds to actually create that building.

Now that I'm in that class, me and my friend now have to make our own year long project similar to that which will take the entire school year to complete and benefit the school in some way that we could actually create, any ideas?

I've had a few but I'm struggling to come up with something that's both on a similar scale to the previous year's project but also viable for literally two people and realistically achievable.