Can you give examples of good resume objectives for students?

Yes. Good student objectives name a specific role, mention a relevant course, project or activity, and say what the student can offer.

Examples:

• Retail: "High school student seeking a weekend sales assistant role. Experienced in helping customers at a family business and comfortable using a card machine."
• Office internship: "Second-year business student seeking a summer office internship. Organised events for the university's business club and confident with Excel and PowerPoint."
• IT: "Computer science student seeking a part-time IT helpdesk role. Built and maintain computers for family and friends and completed the CompTIA A+ course."
• Hospitality: "Hospitality diploma student seeking a part-time waiter role in a hotel restaurant. Trained in food safety and table service during college practicals."
• Tutoring: "Mathematics undergraduate seeking a tutoring role for secondary students. Tutored three students through their exams last year."

Each one is short, specific and honest. Change the details to match your own experience and the job advert.