The present study tested 1) whether children’s bedtimes, wake times, and sleep

durations change as they transition into kindergarten (TtoK), 2) if changes to children’s

sleep schedules were contingent on their pre-kindergarten (T1) napping status and if T1

bedtimes were related to fall (T2) and spring (T3) bedtimes and durations, and 3) whether

T1 sleep, changes to sleep from T1 to T2, and concurrent sleep quality were related to

academic achievement and participation in 51 kindergarteners. It was hypothesized that

1) wake times would be earlier and sleep duration would be shorter during kindergarten

(T2 and T3) than at T1, 2) children who napped at T1 would go to bed later and have

shorter sleep duration than their non-napping peers and T1 bedtimes would be positively

associated with T2 and T3 bedtimes and negatively associated with T2 and T3 durations,

and 3) more optimal sleep (e.g., consolidated, consistent, and high quality) would be

positively related to academic achievement and participation. Parents reported on

children’s bedtimes, wake times, and nap lengths during T1, T2, and T3. During T3

children wore actigraphs for five consecutive school nights and completed the Woodcock

Johnson tests of achievement (WJ-III). Teachers also reported on children’s participation

in the classroom during T3. Results demonstrated that bedtimes and wake times were

earlier at T2 and T3 than T1. Duration was shorter at T2 and T3 than T1. Additionally,

napping was unrelated to bedtimes and durations, but T1 bedtime was positively related

to T2 and T3 bedtimes and negatively related to T2 and T3 durations. Finally, T1 nap

length, change in bedtimes, and Actigraphy duration were negatively related to

participation. Actigraphy onset variability was positively related to participation.