Simple, quick, and a nice size to use almost anywhere.

An old gardening neighbor, years ago, told me, "Make sure you have a place to sit on every side of your house, to enjoy your yard and nature."  This is a cheap and quick way to help with that.

Last week there was a baby shower at my house.  In addition to my kitchen-table chairs, I have about four folding chairs, which clearly wasn't going to cut it for the 43 who were invited.  What to do? 
About a week before the party, I happened to be flipping through the January/February 2011 issue of Fine Gardening magazine. (Reviews here, cheapest here.)
The magazine had instructions and photos for a “one hour bench”.  It looked very simple, and I have a big pile of old boards sitting around, so I decided to build three.  We didn't have exactly the right size boards, but made do.  For instance, the top is supposed to be made of two 2x8's.  I had 2x4's and 2x10's, so I used one of each.  It was time my 13-y-o learned how to build something.  He pulled out the table saw, then measured and cut with me.  (In hindsight, a chopsaw or circular saw would have been simpler.) I put the first one together while he watched, then he built the other two.  Afterwards, he and a younger son painted on some stain/sealer.  The only thing I had to buy for the project was the screws.  Very nice.

So does the bench really only take one hour?  Well, that depends. The magazine gave a list of what wood you needed, cut to which lengths.  If you went to Lowe’s, and had them cut it for you (which they will), and your wood was already cut, then YES, even a newbie could have this together in under an hour.  You might even get the stain on in that time.

So how did having the benches work out?  Well, they look great, are sturdy, and have been sat on a couple  times, by my kids.  The weather didn’t allow for us to be outside last-minute.  I borrowed chairs from a neighbor to use indoors.  Oh well. 

Upside-down, so you can see how it's assembled.  The 2x2's are the white boards here, sitting flush inside against the legs.  Use two screws to connect the 2x2's to the legs.  Then use four screws to go through the bottom of the 2x2's into the seat boards. 
This way, you have no screws showing on top. 
The 1x6's are connected to the bench by screwing them to the sides of the legs, 2 screws each side of a leg.  This makes a huge difference in the stability of the bench.

For a similar bench, see here or here.  If this isn't what you want, try 'the mega-guide to free garden bench plans'.  Some of the links don't work anymore, but it still has a lot to offer.

Materials list:

1x6 boards, 2 each 4 feet long, ends cut at 45 degrees, for the side reinforcement

2x12’s, 2 each 16 inches long, for the legs

2x2’s, 2 each 11 ¼ inches long, for inside reinforcement

2x8’s, 2 each 4 feet long, for the seat

12  2 1/2 –inch galvanized decking screws, to go in the 2x2's

8    1 ¾ -inch galvanized decking screws, to go in the 1x6's

Stain or sealer, if you want.