Background: School-based health centers (SBHCs) fill critical pediatric health care access gaps but typically require parental consent for enrollment. Families' responses to SBHC consent form outreach efforts may reflect broader school engagement. This study investigated whether SBHC consent form return predicted subsequent chronic absenteeism and school transition, indicators of student and family school engagement. Methods: Multivariable logistic regression was used to compare the odds of being chronically absent or transitioning out of a US elementary/middle school (n = 1917) during 2015-2016 and 2016-2017 for those who declined SBHC enrollment or did not return a consent form, compared to those who enrolled. Results: Compared to enrolled students, those who declined had 78% lower odds of chronic absenteeism [95% CI: 0.09, 0.54]. Families who did not respond had 2.8 times greater odds of their student transitioning out of school [95% CI: 2.15, 3.58] but were no more likely to be chronically absent. Conclusions: Consent form return may predict aspects of broader students and family school engagement.