Is this a good way to share the gender?

I go in for my ultrasound on October 10th where I will hopefully find out if it's a boy or a girl. I'm so excited. I found these ultrasound picture frames at Wal-Mart for only $5, there have pink ones and blue ones and say "I'm on my way" across the top. I was thinking we would buy 2 of them for the grandparents and put a picture of the ultrasound in the frame. We would get pink for girl and blue for boy obviously. Then we will wrap it in a bag of the opposite colour to throw them off (pink bag if it's a boy and blue bag if it's a girl). Does this sound like a fun way to share to them whether they will have a granddaughter or a grandson? What did you do or are planning to do to share it with your family? Thanks.