Pittsburg Unified School District shared the video taken of Ms. Mallari's second grade class at Los Medanos Elementary School on its Facebook page.
The video quickly went viral.
Lizzo's original version is explicit. However, Ms. Mallari changed the lyrics to a more kid friendly. They include lines like, "Let's be great, 'cuz I know we are great," and "I just took an ELA test, turns out I'm 100 percent that smart." Other lyrics focus on helping other students and how to be a good friend.
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Many commenters on Facebook said the video was "amazing," "inspiring," and thanked Ms. Mallari for her creativity to engage children.
In the original song, the artist talks about a romance gone bad.
"I heard the song over the summer and loved it. Iit's been my jam." said Los Medanos second grade teacher Dorothy Mallari.
Each year Mallari chooses a song to start each day with positive energy. She wanted "Truth Hurts."
"I knew when I heard the song that it's definitely not appropriate for a school."
So she re-wrote the lyrics and taught them to her students, which spawned a video posted on the school's Facebook Page.
The kids love it too.
"It makes me feel happy in the morning and makes us feel loved," says second grader Hayden Wiebe.
"When we sing the song we forget about all the bad things that happen," added classmate Jose Lana.
"Sometimes personal life gets crazy and as soon as we sing that song it's like a time for us to exhale, be in that moment and feed off each other's energy." said Mallari.