These are benches for outdoor seating, made from recycled chimney blocks and pressure treated lumber. You could purchase new blocks at the home center if you don't have any used ones available. These break down for winter storage.

Step 1: Materials and Tools

Materials

2X6X8 Pressure treated boards (2 for each bench)
1X4X8 pressure teated boards (3 for each bench)
2 1/2" Coated deck screws (I used 3 in each area of the 2X6s, total of 30)
1 5/8" Coated deck screws (I used 2 in each area of the 1X4s, 10 for each board, total of 60)
Chimney blocks (2 for each bench)
Exterior latex paint
Deck stain and sealer

Tools

Power miter saw or table saw
Power drill
Small square
Corner clamps or band clamp
Pipe clamps
Paint brush or roller

Step 2: Cut List

Cut the boards as shown in the diagram.

Step 3: Get the Chimney Blocks

This is a chimney block. Mine were used, but you can probably pick them up at any home improvement center.

These are approximate measurements. Mine were a little taller and a little thinner.

Step 4: Paint the Chimney Blocks

Paint the blocks, inside and out. I used exterior latex paint.. I used a very thick nap roller and touched up with a brush.

Step 5: Make a Box Frame

Make a box frame by screwing (1) 20" board on each end of (2) 42 1/2" boards

Use the square to make sure all your corners are 90°.

Step 6: Attach Inside Bracing

Screw (1) 17" board 9" from each end of the frame. Screw the remaining 17" board in the center of the frame. Make sure the tops of the boards are flush (even) with the top of the frame.

Step 7: Attach the Top Boards

Cut the 1X4X8 boards to length and attach them to the top of the frame as shown in the pictures; overlapping the sides an equal distance all around.
I found the easiest way was to place all the boards and clamp them in place; then screw them down. I used 2 screws in each board, over each 2X6 (total of 10 per board).

Step 8: Assemble the Bench and Stain

Stand the chimney blocks on end and place the seat over the blocks, so they fit into the 9" spaces underneath.

After the wood has "dried" for about a month, it can be stained and sealed. Use it as is until then.