Having actually read the article, I cannot fathom what is more stupid. That they do this, or that they have some weird education funding scheme that encourages this.
I can think of multiple reasons to have children wear locator chips, primarily for safety. However, doing this just to check if they are in the classroom at the start of the day is stupid, especially with the scope limited to just the school and seemingly just the classroom.
On a personal note though, I actually do not have a problem with school children being required to wear locators. It can be instituted as part of a student ID card and part of the students uniform. It can have a verity of benefits. I personally see school as a public enough environment that personal privacy is really not a relevant issue. In a world where students can be abducted or have accidents on their way to school and such, being able to locate them quickly and directly can be of great help. Like I said this is my personal opinion on the matter.