Sippy cup for breast milk?

Hi all - my almost 8 month old used to hold her own bottle at home and at daycare but now will refuse the bottle unless someone holds it for her. I don't mind holding at home but they can't sit there with her at school and do it. They suggested trying out a sippy cup because they think she wants to be sitting up and playing rather than laying down and eating. Any good sippy cup recommendations or other thoughts to handle this? Thank you!