first, the science building was designed by rafael moneo, a winner of the Pritzker Prize.
second, lerner was designed by then dean of architecture bernie tschumi, one of the leading conceputal architects of our day especially in the deconstructivist school.
so just because you don't know anything about architecture, doesn't mean you should start spouting off your thoughts. are they functional, purposeful and unique? yes?
but i don't see you complaining about Frank Gehry's leaky building at MIT with similar vitriol.
as for the architecture department - it is defintely a leading school, probably most known for being the most theoretical department within the top 5 (that now includes yale, harvard, penn, columbia and mit). the ugrad though is not the rigorous B.Arch nor does it come with a combined M.Arch program as of yet. but of my friends who got their BA in Architecture many are at top programs or working for top firms (SOM, RAMSA, etc.).
if you want to see a building designed by a columbia alum, check out:
Broadway Residence Hall - Robert A.M. Stern Architects. not quite designed to stern's original plan, but quite nice.