School Clothing Business

Recently my school created a business club that I joined. We are essentially going to be simulating Shark Tank. My group decided we want to sell clothing with like our school logo on it. The issue is that we want to use good quality material but still sell it for a reasonable price while making money. We looked into different websites like Shopify that partners with printful but clothes would be have to be way to expensive through those sites. Any suggestions of good companies/sites/whatever else that would work well?