This study investigated the effects of a multi-pronged approach of increasing the nature of science (NOS) understandings of high school science students. The participants consist of 63 high school students: 31 in the intervention group and 32 in the control group. Explicit/reflective NOS instruction was imbedded within authentic inquiry experiences and supported by online discussions. The students in the intervention group were prompted to engage in various discussions focusing on essential tenets of NOS in an online environment that assured student confidentiality. NOS views were assessed through multiple data sources including pre- and post-intervention questionnaires as well as students' responses to online discussion prompts. Results show that the instructional intervention used in this study which combined explicit/reflective NOS instruction with intense inquiry exposure along with ample reflective opportunities in an anonymous online discussion format led to positive learning gains in participants' understanding the NOS aspects assessed. Implications for enhancing data collection with high school students and for promising professional development opportunities for science educators are discussed.