When I worked in an elementary school I often had this problem with my special ed K students. I would spend some time in the class playing with them, reading a book to the class or doing a craft. We would also have them be the "helper" and have them walk down with another student who didn't feel well or had to take meds. I vividly remember one student who needed an abrasion treated, she put bandaids on me and her aide and then let us take care of her. We became friends after that and she trusted me when she didn't feel well.