Also, perhaps the "nursery" could just be a designated room from some item like a bed or crib from a baby... I know I stated this before, but stay with me now...
There are three stages of dwarf currently... Baby, child, and adult. The nursery would, obviously, cater to babies and would simply be a place the mother could put their baby to socialize with other babies (possibly forming friendships or acquaintances), periodically returning to check up, visit, and feed their child. The mother would still be an integral part of the baby's life until...
They mature into children! The children could then get a periodic task akin to "sleep" or "eat" that could be "learn" or "go to school" or "attend creche" or whatnot. We could then designate a new type of room from either table/chair sets or a new "chalkboard" type item... Each table/chair set would function as a desk and the room itself would be a classroom where child dwarves learn about dwarven society and the history of the fortress!
Alternatively or additionally, we could have a children's creche sort of building that functions like a daycare or nursery. Either the creche sort of acts to "corral" a specific number of children, or it also functions as a sort of schooling center. Kind of like how kindergarten was half school and half daycare.
I am a fan of the economy system in Dwarf Fortress, including the production systems and engraving/encrusting/studding systems... I think generational fortresses, especially, need to be able to carefully manage and protect their children. This seems like it would be the most expedient way to do it.