the tattoos you could possibly get away with; you'd have to loose the visible piercing they wouldn't go down to well here, particularly at a school.
the only piercing that i have seen here which seem to be acceptable is the Hindu women who sometimes have nose piercing, but this is more acceptable as it is a cultural practice.
the three links i sent were the tip of the iceberg
the issue of piercing and tattoos comes up every two or three months, and normally ends up in heated debate over the topic.