It's pretty normal for kids to behave differently when in school and at home as they are developing a social sense.
In school, they're usually under 'peer pressure' as everyone eat at the same time etc and you do what everyone else is doing to fit in.
Usually kids are more naughty at home because they feel safe enough to act out at home. Slowly talk to her and show her you're eating and enjoying your food too? Kid's love to imitate us so if she sees you enjoying the food, she probably will too! 😄