1. School
Ensley1 by kabdad, on Flickr

2. Office
Bullock3 by kabdad, on Flickr

3. Plant
Bullock2 by kabdad, on Flickr

4. Field
MB3 by kabdad, on Flickr

Very nice colors and tones, just the right amount of contrast. The first two could stand to be squared off, and while the angle looks deliberate, I don't know if it really works, especially for #2.

I think the tone and lighting is very good. Composition is good, i would say just focus more on your lines (horizontal/vertical on your next shoot.

Vibe in the no2 is very nice, good shot.
(this one would have needded to be tilted just a few degrees down)

I like what you were going for in #3

I really like the ambiance and colours. But as others have said, the edges of your photo must be parallel to the horizon or other salient horizontal/vertical features. If you're going for a tilted effect, then really go for it. It's all-or-nothing: it can't look like a careless composition.

I'm still pretty impressed though!

Wonderful pictures. I love the first one. Theres just something the moss that makes it a perfect mix of industry and nature.