Step by Step Instructions:

1. Build the center of the fish’s body using rectangles, window tiles, and small squares. Take note, I used the rectangle (size of three squares) as an important middle base for this build. This helps make the build sturdier. The upper parts on both sides of the rectangle body are open. As an alternative, you can use two 3-square rectangles to form the front and back part of the rectangular body.

2. Now create four trapezoid shapes on both sides of the body using two right-angle triangles and a small square each. They form the head and the tail of the fish. Close them by attaching a window tile in the middle and a small square tile on the top. Leave the bottom part open. The window tiles in the middle are great as internal support for the build because they weigh less than the squares. 

3. Use four small triangles to form the mouth of the fish in the form of a small pyramid.

4. Build the caudal peduncle of the fish (the thinnest part of the fish’s body before the tail) by forming a 3D triangle using two small triangles and a small square. Note that the bottom part is open. Adding a small square at the bottom would make the build heavier and unstable. Connect four isosceles triangles to form the tail fin (called the Caudal Fin).

   Did you know?
   The caudal fin or tail fin provides the power to move the fish forward. The fins come in a variety of shapes – forked, heart-shaped, square or rounded. The shape corresponds to the cruising speed of the fish.

5. Attach two quarter circle tiles on each underside of the fish to serve as the Ventral or pelvic fins.

   Did you know?
   The pelvic fin stabilizes the fish while swimming and allows for up and down movement in the water? The fish use their pelvic fins for floatation, sensory perception, camouflage and for reproduction.

6. Attach two big equilateral triangles as the pectoral fins on each side of the body.

   Did you know?
   The pectoral fins are used for fine movement backward and forward.

7. On the back of the fish, attach two small triangles and a small Square as the main base for the dorsal fins. Use the long right-angle triangles to build the dorsal fins.

   Did you know?
   The dorsal fin or top fin is used in balance, but its main function is usually protection against rolling and to assist the fish in sudden turns and stops.

Have fun learning while playing!