S.E.
I gave my nephew $50. But for friends children I given quite a bit less, depending on the relationship. A high school graduates gift should always be more that an 8th grade graduate. An 8th grade graduate giving tickets to the movies or Walmart gift card is nice. High School graduates are going on to college, 8th grade graduates are just going to high school and in 4 years you will get another announcement.
Take each announcement and look at who they are in relation to you and really go on that basis.
There you have it my 2 cents.