South of Dutton you should be fine, north is where this get marginal. Stay off the main street such as 98th, Bancroft, and even MacArthur, Foothill parrallel the freeway is better than those previous mention. There's not a whole lot of residence street that can get to your High School unless you take those West of MacArthur and those are very questionable.
The suggestion of a beater bike is very advisable. Even a nicer bike locked up at school is a greater target for theft. You mention road team, see what they have as suggestion for your route or of any safe lockable place if you elect to ride your nicer bike.