reporter: nazar said he couldn t sleep, thinking about his kids trapped in mariupol collecting rainwater to drink, cooking over open fires he made multiple trips rescuing nearly 100 students and their families, like maxim and his mother if it weren t for nazar, do you think your life might have been in danger yes, of course, because two days after we left mariupol, our house was burned this is the first of my students and they grew up with me and all our school grew up. we made it together. reporter: nazar s old school now destroyed. but with his students safe, he s determined to keep dancing. matt bradley, nbc news, zaporizhzhia, ukraine. remarkable. that s nightly news for this thursday. thanks for watching. i m lester holt. please take care of yourself and each other. good night