Home office: Perhaps the full-wall shelving unit goes on the wall between the new office and current office? Then the window wall is left without built-ins around the window and the adjoining wall is open for artwork. It would look bigger.
27 Inspirational Homework Areas and Study Stations
One way to ensure both girls have some desk space. Could be done as a builtin or as a removable desk/hutch combination. This has some potential in their room(s) or in some common area where they can do homework.
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