There has been a dispute between my colleague and I between the use of a phrase in our club advertisement. We are a chemistry interest group and sometimes, I feel that new students may feel that the chemistry we do in the club may be difficult etc. Thus, I would like to add in the club advertisement that the chemistry we learn about is "simple-to-understand". However, my colleague says that the word "simple" puts people off as it makes people think that the chemistry we learn about is too simplistic and boring. This is making me extremely annoyed. So I would like to ask about the effect of the phrase "simple-to-understand" on the reader? Does it make the sentence better or worse, in the eyes of the new student?
Note: The target audience is an incoming batch of new students to the school. This advertisement's purpose is to help the club attract new members. The whole sentence is "... members are able to learn interesting and simple-to-understand chemistry outside of the school syllabus".