On Friday night, two 13-year-olds stole a school bus from Western Heights Primary School.
Senior Sergeant Dennis Murphy of Rotorua police said they broke into a locked garage on the school grounds.
"They then drove it through the [closed] garage door."
Neighbours who were alerted by the noise called the police.
Murphy said police apprehended two teenagers a short while later after the bus had been driven 50-60m across the school grounds.
Police have referred the incident to Youth Aid.
Murphy said officers have noticed an increase in thefts from cars and properties.
The highest hit area has been the southern end of Fenton St and Fenton Park.
"We are urging people to be vigilant," Murphy said.
"Secure your property and vehicles."
Meanwhile on Sunday night, police received a call from neighbours concerned about a "loud argument" going on at a Hillcrest address.
"When we got to the address, we located 96 cannabis plants," Murphy said.
He said the plants were all inside a large vehicle parked at the property.
"Police advice in this situation is not to start loud arguments if you're growing dope," he said.
A 38-year-old man has been charged with cultivating cannabis.