What is the ruling on watching children's channels (Nickelodeon, Karameesh, and Toyor Al Janah) and cartoon movies such as "Tom and Jerry"? And are they part of the Jews' plot to corrupt children?

The basic ruling on watching cartoons and similar media is permissibility. If their purpose is to promote virtue and teach Islamic manners and ethics, and they are free from Sharia violations, then their creators will be rewarded. However, if they are not free from Sharia violations, such as those related to creed or morals, then watching them is impermissible. Parents must be vigilant about this to protect their children from anything that could harm their religion and morals.