Total budget: $385 right?
I have participated in onboardings myself and the audiovisual content I have use is a powerpoint presentation as the following: here and here
I have another question regarding this, audiovisual content was not already created? @Arturoahs in former campaigns? 
The POP material looks good for me, you could use something like the following paper wallet:
As you already have experience in this field, the metrics of success could be meassured on graduated students, and you could add your value proposition as promoter + guide/support/coaching