Of course it is NOT true. A little common sense and understanding of science and evolution will tell you that.
There will always be conflicting information coming from religion and science. The first is based on superstition, archaic beliefs, and mostly fear. The second is based on logic, knowledge, reason, research, intelligence, and a feet-on-the-ground approach.
The Earth was formed "billions" of years ago, and the dinosaurs evolved into being millions and millions of years ago, not just a mere 15,000 years. No one "planted" their bones. It is a "scientific FACT" that these wonderful animals lived and existed LONG before man, and ruled this planet for millions of years.
You are, of course, free to believe what you wish, and so is your teacher. Each and every person should be allowed to believe anything they want if it brings them happiness and does no harm to anyone else. All I'm saying is that what you are being taught by your teacher is NOT logical, and does not make any sense at all in the world of scientific fact.
Professional Wildlife Cinematographer, Photographer, & Naturalist.