I make these simple designs for sale, but lately it seems I've been giving a lot to friends and family... I gotta come up with a better system.
The bookcase shelves/sides and desk aprons/legs are joined with sliding dovetails.
The bookcase shelves and sides are 1x10s, the top is two 1x6s. The desktop is four 1x6s.
I used to worry about using boards as wide as 10s for these applications, but I went to a new
supplier in Amish country (I'm in NE Ohio) and have zero twists, cupping, or crowning any more.