It is a pencil you need for the class, but marker blenders work beautifully with wax based colored pencils too.

However, don't get prismacolor! I've been selling fine art supplies for the last 13 years and their quality has taken a nosedive. Go with Caran D'ache. https://www.amazon.com/dp/B006FXBPQO/ref=cm_sw_r_cp_apa_fabc_7v.9Fb23ES3JF