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The NASA Kepler spacecraft data revealed a large number of multimodenonradially pulsating gamma Dor and delta Sct variable star candidates. Thehigh precision long time-series photometry makes it possible to study amplitudevariations of the frequencies. We summarize recent literature on amplitude andfrequency variations in pulsating variables. We are searching for amplitudevariability in several dozen faint gamma Doradus or delta Scuti variable-starcandidates observed as part of the Kepler Guest Observer program. We applyseveral methods, including a Matlab-script wavelet analysis developed by J.Jackiewicz, and the wavelet technique of the VSTAR software(http://www.aavso.org/vstar-overview). Here we show results for two stars, KIC2167444 and KIC 2301163. We discuss the magnitude and timescale of theamplitude variations, and the presence or absence of correlations betweenamplitude variations for different frequencies of a given star. Amplitudevariations may be detectable using Kepler data even for stars with Keplermagnitude >14 with low-amplitude frequencies (around 100 ppm) using only one ora few quarters of long-cadence data. We discuss proposed causes of amplitudespectrum variability that will require further investigation.

Amplitude Variability in gamma Dor and delta Scuti stars observed by the Kepler Spacecraft