We use a Google Form e-pass. The teacher fills it out, there are check boxes for why they are being sent and one "free space" to write in some details, and then the nurse gets an email notification. The nurse calls into the classroom when it's clear to send the kid. If it is an emergency - asthma, bee sting, etc. - the teacher can call for the nurse to come to the classroom or to send the kid to the clinic.