Desperate family and friends of a "kind and funny" teenager missing at sea have left a makeshift shrine of fruit, flowers and a fish and chip box as searchers scour the coast for his body.

But a close friend is still holding out hope the young man "comes home safe".

Emergency services will today resume the grim search for Melville High School student Jaden Chhayrann, 17, who is being remembered as the kindest friend who would always help people when they needed it.

The Hamilton Year 13 student was caught in a rip while swimming on a school geography excursion at Waihī Beach about 12.40pm on Friday.

A parent told the Herald the teen did not resurface, despite a teacher's heroic effort to save him.

The tragedy comes amid six water-related deaths in just four days.

Heroic mum Kelsi Wood drowned rescuing her daughter from a rip at Kaipara's Baylys Beach on Thursday night. The devoted mother of three died and the child received minor injuries.

Kelsi Wood's heartbroken mother, Susan Fowlie, said Wood gave her life rescuing her daughter from the sea.

Woods was described as a positive, "strong and fiercely independent woman with an intelligent mind and good values".

Kelsi Wood, a mother-of-three who died while trying to save her child at a Northland beach, has been remembered as a hero. Photo / Supplied

On Friday Napier schoolboy Marama Te Pou, a 7-year-old twin known as Boombie, drowned after being snatched by a wave while playing in the surf at Te Awa in Napier.

Another person drowned at Northland's Langs Beach on Friday, the police dive squad pulled a body from the Whanganui River after a swimmer went missing on Thursday night and a man died after going missing in a water incident near Lake Monowai in Southland on Friday.

Christine Moeun, a friend of Jaden's, told the Herald she was still in shock about the Waihī Beach incident and kept wishing it was a dream.

"He was always here to support his friends and family. He was such a sweetheart to everyone, that's what I loved about him. He always seem to make everyone laugh and smile. He was definitely one of the guys I love being around, he was always happy and so funny," she said.

"Still hoping he comes home safe but it really hurts that we can't do anything about it but wait for him to rest in peace beautiful angel."

Jaden loved listening to music, spending time with friends, playing video games and was a fast runner.

Yesterday about 20 pieces of fruit including apples, pears and mandarins, two bunches of flowers and a fish and chip box were placed on some rocks just north of the Waihī Beach Surf Life Saving Club in the teenager's memory.

A beachgoer said Waihī Beach near the surf club was busy yesterday as the water was much calmer than the rough conditions over the previous 48 hours.

A jetski with two lifeguards scoured the rocks about 2pm, she said.

Police are leading the search with the help of lifeguards on IRBs and jet skis.

Melville High principal Clive Hamill said the school was focused on support for the missing teen's family, plus the students and staff involved. The school was preparing a statement to be released this morning.

On Friday the school confirmed on its Facebook page that one of its students was involved in a serious incident at Waihī Beach and was missing.

Ministry of Education deputy secretary or sector enablement and support Katrina Casey said the ministry had offered support to the school and would be available as long as was needed. The ministry is not discussing any investigations "at this time".

"Our thoughts are with the family and the school community at this very difficult time for them."

Waihī Beach was not patrolled by lifeguards at the time Jaden got into difficulty, but lifeguard teams from Waihī Beach and Whangamata were called to help with the search for him on Friday afternoon.

Water Safety New Zealand chief executive Jonty Mills said the past few days had been a tragic time for families and the country as a whole.

The hot summer was making it inviting for people to get in the water at beaches, rivers and lakes, but he warned water conditions could be unpredictable and changeable.

With a diverse population and visitors unfamiliar with New Zealand waters, it was important for people to swim between the flags, Mills said.

National lifesaving manager Allan Mundy said lifeguards worked hard to keep people safe by patrolling beaches, and operating Search and Rescue squads that were activated after patrols went home.

He said no one was stronger than a rip and urged people to "swim between the red and yellow flags and remember the three Rs – relax and float, raise your hand and ride the rip".