The teenager, 15, was set upon by several people outside Thomas Knyvett College in Ashford, Surrey, on Monday afternoon, in what police are treating as a "racially aggravated" attack.
"Shocking" footage circulating online shows the victim being punched and kicked, as well as having her braids pulled from her head as onlookers can be heard shouting "kick her in the face".
Police said more than 50 officers have been investigating the incident or engaging with the community in Ashford over the last three days.
A 39-year-old woman and a 43-year-old man have been arrested on suspicion of child neglect and intentionally encouraging and assisting the commission of an indictable only offence.
The same 39-year-old woman, a 16-year-old girl, and two 11-year-old girls were arrested on suspicion of attempted racially aggravated grievous bodily harm (GBH). In addition, the 16-year-old girl was also arrested on suspicion of malicious communications.
All those arrested have now been released on conditional bail until a date in March.
Meanwhile, officers said they are also seeking another 15-year-old girl in connection with the attack.
The assault has led to public outcry, with protesters gathering outside the school on Wednesday and British rapper Dave calling for all staff featured in the video to be sacked. Sky News