You will not find employment in a lab with a high school degree. Scientists at all levels, from Bachelor's to PhD, are in huge surplus right now and many are having a hard time finding work. Your background will not be competitive with people on the market right now. At best, you might get the chance to volunteer or shadow for a short period of time in a lab. There are some areas of clinical science that only require an AA, but this is still above and beyond high school education.
FYI, PhD programs in the sciences do not cost money, they pay you to go to school. Master's are typically not offered this luxury, although there are ways around this. More importantly, you should be planning for your Bachelor's degree first before you look into Master's and PhD programs. Very few people pick a major in high school and actually end up getting that degree; most change their major along the way, often in a drastically different direction. I've seen many liberal arts and business majors spawned from the first quarter of organic chemistry.