Bianka Vale was a student who made her appearance in Series 5 Episode 11.
Bianka's parents had split up, and her mother acquired a court order saying her father wasn't allowed anywhere near her or her brother.
Gary came into school to take his children, in vengeance against his estranged wife. Michael's teacher, Jo Lipsett, did the proper checks, alerting Rachel, and refused to let Gary take Michael, but Bianka was in English with the lazy Grantly Budgen who let her go without so much as batting an eye.
When Rachel discovered that Gary had taken Bianka, she followed them in her car, as Chris called the police.
Rachel followed Gary and Bianka to a caravan in a field, where Gary treated Bianka to a small celebration for her birthday. Rachel knocked on the door and revealed to Gary that the police were looking for him, but he told her to go away; however she talked Bianka into inviting her to join the mini party in the caravan.
Later, an increasingly unhinged Gary filled the caravan with gas and pulled out a lighter with the intention of blowing it up with himself, Bianka and Rachel inside, purely to spite his wife. As Gary was distracted by the lighter failing to spark, Rachel elbowed him out of the way, grabbed Bianka and escaped the caravan with her, and they ran as far as they could get before Gary successfully lit the lighter and the caravan violently exploded with him still inside, killing himself instantly. Neither Bianka nor Michael were seen again.