Banquet dress?

• 18

What do y'all think of this dress? I picked it up from a thrift store the other day (for $4.50), and am considering wearing it to my school banquet this year (I'm in grade 12, so it's my last banquet)...

It's a full length dress, but couldn't get it in the picture. I would wear at least 4 inch heels with it (I'm 5'6), as that's what it takes so it doesn't drag on the floor.