How To Handle Child Tantrums?

This whole year my 6yr old daughter who attends 1st grade has a complete melt down at school only to the point of throwing herself on the floor when she is unable to be first in line. she has even pushed and kicked other kids to get out of the way. then when she is sent back to the classroom and she is forced to miss recess because she lost time in class for her melt down she escalates her disdain by being disrespectful and refusing to work when told too. But it all starts with her fixation on being first in line for everything, recess, lunch, assembly... ive taken everything away, I tried putting her to bed early, making her do extra math, um spanking as well but she continues to do it and she does it at the home daycare I drop her off at too not as bad because the woman that runs the home daycare is like her 2nd mother and she handles her when she does that so she stops faster. but the public teacher cant handle her you know but she should not have too...