Return from Witch Mountain (1978)

Tia and her brother Tony have supernatural powers, can communicate and move things with the power of their mind alone. They arrive on Earth for a visit in Los Angeles. When Tony uses his powers to prevent an accident, he gets into the hands of Dr. Gannon, a ruthless scientist who's constantly striving for power over the world. He puts him a device into the brain that allows him to control Tony's will. Tia gets help from a kids gang to free Tony and save the Earth.