I like PE class. Because I like sports. In PE class I can do some sports so I like PE class. I like math. Because I like to solve a problem. And I like science. Because I can do a lot of experiments. I like to experiment.
NOTE: you're good in making sentence, but I suggest to try to use synonyms of words to avoid repeating same words ex: instead of saying "I like PE class. Because I like sport. In PE class I can do some sports so I like PE class". it's better to say "I like PE class, because I like sport. In this subject I can do some sports so I like it".
also be mindful of the usage of singular and plural words,
Goodluck! Enjoy learning English, you can do it!
