My 4 year old keeps sneaking into things?

She just started Pre k this year and she had some problems with going at first. She would cry an didn't want to stay, then she wanted to go an stay but she didn't want to come home. Now shes fine she goes to school and she comes home but she's started sneaking into everything she sneaks into the bathroom and into my bedroom and gets ahold of my jewelry and hair ties an she got ahold of my chewable gas tabs on my night stand in the morning she snuck in my room an didn't wake me up (she used to wake me up and mind you she wakes up at 6am) and ate 3 of them luckily that was all that was left! I'm getting close to just homeschooling her so she stops picking up these kids bad habits. Has anyone gone through this? is it a stage? are there better ways to discipline her that don't require hitting I've tried time outs an taking things away i've tried talking to her at her level and telling her mommy don't like when she sneaks into stuff but she just continues to do it I am a stay at home mom so she's getting plenty of time with me so I don't think it's her trying to get attention we do everything go to the library, parks, zoo, museums...(ect.)