This is a nice first project.
That combined with a report on the history of oscillating steam engines would be good. You will find that while now saying oscillating steam engine is the same a saying toy engine, at one time there were some very big oscillating engines in use, the Great Eastern used them to turn it's paddle wheels.
This one is a bit more complicated, more operations you have to think thru ahead of time because sometimes doing one operation before this other one can make a third op very difficult.
They also have a number of other engines and a neat line of kits for make little model machine tools.