All the students are very ---- .(excit)

exciting:adj.
令人兴奋的, 使人激动的
主语是物或事
e.g. This movie is so exciting.
这部电影真让人兴奋、激动.
excited:adj.兴奋的：处于激动状态的；兴奋的；激昂的
主语为人较多
e.g. she's so excited about the upcoming holiday.
对于即将来到的假日,她兴奋不已.