Buisness at school.?

Is 5 Dollars for a laser pointer with 5 heads included with batteries a reasonable price to sell to students at school in high school and do you think that it will sell a lot. And also should i sell laser pens with a blue led light for 10 dollars or 7 dollars. I am buying these items from a wholesaler. And am looking to make some profit. Im only 15 and have a debit card if that helps any.