Instruct: Classify a review as either positive or negative.
Query: Feels cheap, doesn't focus

I purchased several $6 and less "field microscopes" off of amazon to test them against one another. My goal is to find one or two models that are suitable for a homeschool co-op class of 6-10-year-olds. This one failed right out of the box. It was the most expensive model, with the lowest magnification, a useless focus knob, a cheap build quality, and no batteries to power the light. I requested a refund 10 minutes after opening the package so hopefully the seller will oblige.