27 September 2016 Last updated at 07:16 BST
The 15-year-old won an incredible gold medal in the women's S6 50m butterfly in Rio, setting a new Paralympic record with a time of 35.58 seconds.
She also came third in the S6 100m freestyle final, winning a bronze.
Watch Ellie's classmates and teachers give her a special welcome on her first day back at school.
Ellie Robinson is the star swimmer who's returning to school this week as a Paralympic champion.