I first want to say that it is normal for children to hit. It is possible she's learning this behavior at daycare, however, I would talk with her daycare provider about this issue and how he/she handles it in the classroom. As a childcare provider for over 7 years now [5 years in a daycare setting] I know from person experience that my following suggestions will work if you are consistent.
Instead of telling her "no" or "no hitting" etc, tell her what she should be doing.
For example
She hits mommy/daddy:
Take her hands gently in yours and tell her, “our hands are for hugging" or “our hands are for blowing kisses" etc
She throws her food on the floor:
Tell her "our plates stay on the tray" and put her plate back on the tray to show her.
I would also suggest teaching your child simple sign language, like "all done" or "more" these signs are very helpful in knowing what your child wants before he/she can speak [I was skeptical at first too, but trust me, it works if your consistent!]
when you tell a child "no" they may not understand that you are referencing the hitting, he/she may think you are talking about the way they are standing, they may have just blinked, or think your mad at the face they just made and has forgotten all about the hitting, so use positive reinforcement. If she gives you a hug, say "I love that you are using your hands for hugging" etc
I challenge you to take the word "no" [or words similar like cant, or don't, etc} completely out of your vocabulary for a week and I believe you will be pleasantly surprised! You may think you sound silly, but once you get use to it, IT WORKS WONDERS!
[You may also want to try suggesting to your child’s daycare provider these same tips if he/she is also concerned about this behavior. Use cautions in your approach, some teachers believe they have everything under control and become territorial. We don’t want to harm the relationship you have with him/her. You may want to try this at home and then tell the provider about your positive results]
I hope this helps you and your family
-MP-
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