Yes you may, claim on laptop and cellphone. Please bear in mind, you need to apportion the claim between business and personal use and keep records to justify the apportionment in case SARS queries it.
Regarding the car, again you need to apportion between business and personal use. Also please note you may not claim the distance traveled to work (school) from home and back as part of business mileage as this is considered personal travel by SARS. Only business trips done from the school to other offices or places of work can be considered business travel. In addition, you must keep a logbook detailing all travels. The opening and closing km's for the tax year as well as all the km's you traveled purely for business purposes must be recorded. Also keep all the details of the car you used!
Please make use of our wear and tear calculator below to find out how much you can deduct based on your % business use and type of asset.