The six, all friends from the same Phuket City school, found themselves in difficulties at the southern end of the beach, near the passage that leads to a lagoon, about 2pm.
Locals who know the conditions at the beach well joined in to help bring all six safely to shore.
Two of the friends, who were on a picnic on a day-off from Phutthamongkolnimitr School in Phuket City, were admitted to Vachira Hospital in Phuket City. They are Boonrit Boonma, 15, and Kammolrat Daman, 14.
The two were being given oxygen and appeared to be responding to treatment.