The technique for the smaller block is fairly similar to the ones used for the larger block, but there are a few differences. Since the block is so small there's no need to pin at the middle. The horseshoe piece goes on bottom and the pie piece goes on top. Begin by matching up the starting ends and doing a few stitches.
Just like with the larger block, straighten out the block as you sew so that when the seam passes under the needle it's a straight line. You'll tug the top piece a little to make this happen, but be careful about tugging too much. Because the curve is cut on the bias it has a lot of stretch and your ends won't match if you tug too much.
Because of the size of these blocks getting the two pieces lined up was a challenge at the end. I found a pair of tweezers were great for finishing out the seams. (Some of the ladies at the workshop used tweezers on the bigger blocks too, but I didn't find that to be necessary.)
Alternate the direction you press so that your seams will nest. (I pressed the tail and head towards the white and the back and belly towards the blue.) This block hasn't been stitched but it gives you an idea of how the fish will look.
Since I neglected to share my penguins last week here's one of them. Four fish blocks equal one penguin.