This is the high school I went to. We were very lucky to have such a great science program. Keep in mind this is a school with less than 100 students in a town of about 450:

In the small community of Sunburst near the Canadian border, North Toole County High School teacher Larry Fauque accompanied four of his students to ISEF. Fauque estimates this was his 20th trip to ISEF. Three of his four students won awards at this year's national level of competition. The National Science Teachers Association has recognized Fauque's science curriculum over the last 34 years as one of the top 10 science research programs in the nation. Link

We might not have had AP classes, but classes like this made up for it. I'm also confident our English and Math curricula were as strong as most schools' AP curricula.