I loved this video because it touches on many essential elements of a successful lesson, especially introductory. I also liked the activity shared by Mr. Jim Paige.

What about coming from the direction of area as an exploration? Students start with a square of known area, say 10 cm X 10 cm. Then they create 2 areas from the square such that the sum of these areas equals the sum of the original square, say 80 square cm and 20 square cm. For each of these areas, they create squares of equivalent area. For 80 square cm, the side length would be 8.94 cm, and for 20 square cm, the side length is 4.47 cm. Students draw and cut out all three squares and use the sides of each square to make a triangle. The purpose would be to physically and mathematically establish the area of the squares relationship for a right triangle. Many different right triangles would be created because students will end up with different sized smaller squares than their classmates. The activity might prevent students from a simple (and incorrect) relationship between side lengths for right triangles.

And from across the proverbial pond, I like this way too https://www.teachingchannel.org/videos/teaching-pythagorean-theorem