Sloan

Sloan was Ralph's best friend from school, whom he had a crush on.

Love Boat
Ralph wanted to give her a valentine, but was too nervous, so Happy and Toby help him shoot off fireworks, and she is seen enjoying them and talking to Ralph.

Arrivals and Departures
She looks at Ralph after Cabe picks him up so he can help save Team Scorpion. Cabe remarks the line, "Don't worry the girls gonna dig it." and Sloan indeed does look Ralph's way as numerous other students are whispering.