Sounds like you both did great today. Your teacher is proud too.
Literal
Two-people both today [topic-は] great-performance was [seems-みたいね]. Teacher [also-も] nose [subject-が] high [feminine-わ].
大活躍 'great performance/achievement.' 鼻が高い 'to be proud' is an idiom — literally 'nose is high,' evoking the image of holding one's nose up with pride. みたいね is casual hearsay/inference. The feminine わ marks the speaker (likely a female teacher or parent) expressing warm pride.