where your hands dog made you put the gun up this is "nightline." >> tonight, hard hits. on the football field. leading to more concerns over concussions. are high-tech helmets and teaching players the safer way to tackle the right strategy? meet the trumps. an intimate look at the donald. a look at the family and life with melania. >> i know what he can do for the country. >> the first interview together since trump announced his bid for the white house. could this be the new first family? i am here with all my friends. >> one teacher's morning compliments go viral. >> you're wonderful you're fun.

>> how he's using the powerful message to light up the classroom. but first the "nightline 5." >> how else do you think he gets around so fast? take the reins this holiday and get the mercedes beps you've always wanted for your winter event. hurry, offers end soon.

xt1 plain good evening. thank you for joining us. it's friday night and all across america, all too many parents are holding their breaths on the football sidelines. as concern rapidly intensifies

field. can new helmet technology and new coaching tips lessen the impact of those violent hits? here's abc's ryan smith. >> reporter: when jordan one thing on his mind. football. dalton, number 71 for the north wood high school chargers, is a senior on the varsity team. identified as a high-risk player. high risk for concussions the field. but it's those hits on the field that worry his mom cara. >> when i see jordan get hit, i'm usually thinking about how hard was that hit? concussion? was it hard enough for a concussion? that's the part that i don't really know. >> reporter: across the country parents like cara are questioning just how safe the game is. preoccupied a big hit could land their son in an emergency room or worse.

since july there have been 11 high school fatalities, seven directly related to a traumatic injury. the most recent? >> slipped past a tackle -- >> reporter: luke shem, number 4, scoring in a playoff game two weeks ago after taking a hit in the third quarter and running off the field, shem collapsed, was flown to a hospital where he died the next day after his family removed him from life support. >> our beautiful gift from god months longer with us. >> reporter: tonight another high schooler in southern california still recovering at a medical center four weeks after what appeared to be a routine tackle. dramatic video showing josh nava stumble off the field. needing emergency surgery to stop the bleeding, swelling, and pressure on his brain. >> he looks like he's in pain. >> reporter: little is known about how hard nava was hit but the helmet he wore contains sensors able to catch that data. but a school official said the

concussions. the long-term effects of multiple concussions or even just one concussion. >> reporter: so is a team of researchers from university of north carolina who determined jordan to be an at-risk player for head injury. hard hits to his head from early in the season flagging him, turning him into a subject in their three-year study aimed at reducing the risk of concussions. revealing a lot more than cara knew. >> i didn't realize in the beginning that he was the one getting more impacts than anybody else. impacts mean. >> we're trying to better understand if we can change the behavior on the field. >> reporter: dr. kevin goskowicz leads the study known as bemo, short for behavior modification. >> this is footage of teams in our study. they have this system in their helmets. >> reporter: researchers track, in realtime, the number and strength of hits to players' heads. that data, some of which is shown in this video from the

study, reveals who they say may be at risk for concussions. >> what's 95-g like in the context of a car? >> 25 miles an hour. >> reporter: coaches staged an intervention with jordan, focusing on drills to help him understand what's seen as a safer way to play. how-to videos. it's based on a method of tackling and blocking known as heads-up football, an nfl-funded and promoted program emphasizing shoulders when tackling, not with their heads. a recent analysis found players between the age of 5 and 15 playing on teams adopting the program had a 76% reduction in injuries and a 29% reduction of concussions during games. jordan works on his form during specific drills at practice. and then reviews video of it from previous games. >> the impact that you took on this play was an example of a 95-g hit. >> my stance is terrible and i'm

tackling with all their might, all their force. they don't want to think. the right way? >> the message we're sending is you've got to play smart today, to be able to play later. >> reporter: he showed me video of jordan from early in the season which he says shows poor form. >> what's he doing wrong? >> well, you can see he's head to head right there. that's a high impact. >> reporter: he compared to it a lights. >> same exact play but you're going to see he's going to get out? front, going to get those arms up a little earlier. at impact that's better clearly technique. >> reporter: he's part of the nfl's head, neck and spine committee. and dismisses scrutiny arising from his nfl connection. >> you're on an nfl committee. are you concerned that some people will see your results and be do you remember yus of those results? >> i'm an unpaid consultant or advising them about what we see as ways to ilprove safety in their sport.

trying to make a difference at this youth level. >> reporter: and he's not the only one investigating a way to make the game safer. eric schwartz, former rugby player, knows tackles in that game almost never involved the head. >> your thought is if they learn it without the pads, rugby style, they won't do it as much during the game. >> we hope it will carry over. it eliminates one player from basically turning their body into a projectile to blow somebody up. >> reporter: known as helmetless tackle training, he used university of new hampshire wildcats as test recruits. and he says there's some early evidence it's working. >> we've been able to identify that some of them actually decrease in the number of impacts per exposure. >> reporter: eager to help younger players, swartz approached a nearby high school and enrolled them in a study.

wired with monitors they practiced tackling without helmets and pads. unh researchers counted more than 50,000 head impacted this season. >> how many times cab a high school player face contact in a game? >> they can receive 30, 40 impacts to the head in a single game. >> reporter: swarts' catching the eye of ge, under armour, and the nfl, all co-sponsors of his study. >> i understand there is a level of scrutiny and skepticism. i get that. that was just one of the opportunities that was available that we pursued. >> reporter: these studies coming at a time when numbers of high school football players are decreasing. last season there was nearly 10,000 fewer high schoolers playing the game than the previous soap. season. still, football is by far the most popular team sport in high school. >> you've turned on the lights and gave their biggest positiony man a name. >> reporter: dr. julian bales, played by alec baldwin in

"concussion," a neurosurgeon and one of the leading surgeons on traumatic brain injuries. >> sensors, smart helmets, having weekly hits is all important. hopefully technology is going to be a big part of solving this concussion issue in sports. >> reporter: many agree nothing can eliminate the risk of taking a big hit on the field. >> do you worry about facing one of these life-threatening injuries on the field? head. if you get hit you might think, that could be something. but you have to keep playing. >> reporter: for "nightline," i'm ryan smith in pitsville, north carolina. next, an abc news exclusive. barbara walters with donald trump and his family. the children telling us what life is really like with the

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test message cc1 this is the donald trump you'll rarely see. home with his wife ask children and grandchildren. a family portrait with wife melana in their first sit-down

husband announced his bid for president. >> our leaders are stupid. stupid, stupid people. >> reporter: donald trump is a candidate like any other. >> bing, bang, bong. >> you speak your mind and you have sometimes offended women, latinos, veterans. how can you unify the country when you make these divisive statements? >> women respect me, they like me, they know i'm going to take care of them. aim going to protect them. the people that are here legally, hispanics, like me because they don't want people coming in ask taking their jobs. >> do you speak any spanish. >> no, this is an english-speaking country, remember? >> what's the downside of being part of the 1% of the richest people in america, especially when you're trying to reach the middle class? >> the funny thing is, i'm a rich guy but i have this great relationship with the working people of this country. and that's true.

>> reporter: donald trump has always set the gold standard, literally, for life at the top. his $100 million tri-level penthouse is inspired by versailles. >> you have said that success is a kind of drug and it's too powerful for most people to handle. how do you handle success? >> well, a lot of people can't handle success. i've seen it. a lot of people don't know how to win. >> reporter: he shares this palace in the sky with his beautiful and graceful wife >> hello. >> reporter: she has been mostly absent from the campaign trail until tonight. mrs. trump, it's a pleasure to see you and we don't see you that often. you're not on the campaign trail. how do you feel about campaigning? >> it's my choice not to be there. i support my husband 100%. but we have a 9-year-old son together. barron.

i'm raising him ask this is the age he needs a parent at home. >> were you involved in the decision of your husband to become president? >> we discuss a lot, yes. i encourage him. >> you did encourage him? >> i encouraged him because i know what he will do and what he can do for america. he loves the american people and he wants to help them. >> reporter: if the trumps win the white house, melania will have two noteworthy distinctions. the first foreign-born first lady since john quincy adams' wife louisa, and the first first lady to have posed in a picture like this. >> i don't know how to put this. your image looking the way you do, is that a liability for your husband? >> i don't think so. i don't think so. i think people will always judge. maybe they will say, oh, the past that you have, the way you were modeling. that's part of the job that i was doing. i was a very successful model. >> reporter: it's been ten years since donald and melania said i

do in a lavish affair at trump's miralago estate in florida. this is your third marriage, what's different this time? >> i think i understand life. i've gone through tremendous amounts of everything. deals, building companies, taking care of people. >> how does that help marriage? >> it hurts marriage because you're working all the time. >> your husband has been married twice before. did you have any concerns it might not work out? >> no, i didn't have any concerns. we have a great chemistry. and to be with the man as my husband, you need to know who you are, you need to be very smart and quick and be there for him when he needs you. >> is yours a marriage of equals? >> i would say, yes. >> i would say no, no, i think she's far greater than the 50%. no, we have a very -- a pretty much equal relationship, wouldn't you say? >> reporter: i wondered if melania has ever taken his husband to task on his tone

>> did he make a derogatory comment attacking carly fiorina? >> i think women all over this country heard very clearly what mr. trump said. >> you know your husband has come under fire here and there for making disparaging remarks about women. does this bother you? >> it doesn't bother me. he treats everybody the same. he talked about men as well, not about women only. maybe they just go into a little bit more details when he says something about women. >> reporter: i sat down with donald trump's four oldest children. donald jr., 37. ivanka, 34. eric, 31. tiffany, 22. has your father ever said anything on the campaign trail that made you cringe? >> truthfully, no. >> no, no, no? >> he's true to himself and he speaks in a way that the average person can understand. it's refreshing for everyone. >> reporter: tiffany, trump's

marla maples, is a senior at her father's alma matter, university of pennsylvania, with plans to go to law school. >> people are meeting you today many for the first time. to grow up with the name tiffany trump, that's not easy. >> it's all i know. i'm so happy to be tiffany trump. so happy to be in the family i'm in, with my siblings, my father, my mother. >> reporter: they say their father taught them to respect the value of a dollar. >> to say we weren't spoiled would be laughable but we were spoiled with great education, great experiences. we weren't the kids showing up to college but a ferrari. we always had to earn whatever it is that we wanted. >> reporter: and it seems the donald trump work ethic is in their dna. >> we refer to it as the trump guilt. when we wake up on saturday and we're not working. >> your father has said he was not, using his words, very present when you were growing up. >> i would challenge him on that. because he was very available to us. >> from when we were 6 years old, he'd been negotiating with

whatever, and he would make them wait, and take the call from us. >> our times together were learning. no playing in his office. he'd sneak me down to get a candy bar in the lobby. >> reporter: it's a very different side of donald trump. the soft one. breaking from the daily grind to greet his seven grandchildren. >> look at this, what a troupe. >> what is your father like as a grandfather? >> he's been great. >> reporter: seems even the littlest trumps are already learning from grandpa. >> a few months ago, walking down the street, my daughter sees a large pothole in the street. she looks at me and she goes, that. she's 4. >> definitely genetics. >> for sure. >> what do you dream about most frequently? >> i have good dreams. having a good life. good family, good life.

i'm looking around this room. the white house might be a step down. >> the white house is the white house. it's just a spectacular place. and, you know, it's something that represents something very special. >> our thanks to barbara. and next, a teacher teaching powerful lessons, lifting spirits one student at a time. >> you're fast, you're strong. thank you for being a good student. >> thank you. p don't even think about it. i took mucinex dm for myt phlegmy cough. p yeah...but what about mike? rhe has that dry scratchy thing going on. t guess what? it works on his cough too. cough!t guess what? it works on his cough too. t what? stop! don't pull me! spoiler alert! she doesn't make it! p only mucinex dm relieves both wet and dry coughs for 12 hours with two medicines in one pill. t start the relief. r ditch the misery. t

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rooms across the country the school day starts with some routine. this florida teacher is showing us the true power of a morning message. >> i am here with all my friends. we've been in the same special education classroom for three years. >> reporter: chris ohlmer, special ed teacher, whose unique teaching style is going viral. >> you're awesome, you're great, you're fun, thank you for being a great student. >> reporter: he starts class with compliments. >> i think everyone in here loves you. great job. >> i think i'd important that they learn how to be kind to one another. so i model that and whatever they see me do, that becomes their reality. >> i can lift myself up and get back in the running. >> reporter: his kindness curriculum has grown outside of the classroom. >> seven months ago i started a blog called special books by special kids. and the reason we started that

was so that the children in my class who have a variety of different conditions are now able to communicate with the world. my goal is to help people step inside the mines of these children. because i think that their minds are some of the most pure i've ever seen. >> i love you too, you're a great student. >> you're the best teacher. >> it was the late norman vincent vincent peale who wrote an entire book about positive thinking. he believed a kind word could lift the soul and change the world. thank you for watch. tune into good morning america tomorrow. as always we're online 24/7 at our "nightline" facebook page and abcnews.com. good >> breaking tonight: the new twist in mysterious

disappearance of a two-year-old.