diff --git a/game-setup-example.html b/game-setup-example.html
index d540758b..84b42f6b 100644
--- a/game-setup-example.html
+++ b/game-setup-example.html
@@ -244,7 +244,8 @@
             const amplitude = harmonics[ i ].amplitude;
             assert && assert( amplitude !== undefined, `harmonic ${order} is missing the amplitude field` );
             assert && assert( amplitude >= -MAX_AMPLITUDE && amplitude <= MAX_AMPLITUDE, `harmonic ${order} amplitude is out of range: ${amplitude}` );
-            //TODO verify that amplitude has at most 1 decimal place
+            assert && assert( ( amplitude.toFixed( 0 ) === '' + amplitude ) || ( amplitude.toFixed( 1 ) === '' + amplitude ),
+              `harmonic ${order} amplitude has more than 1 decimal place: ${amplitude}` );
             const amplitudePropertyID = `fourierMakingWaves.waveGameScreen.model.level${level}.answerSeries.harmonics.harmonic${order}.amplitudeProperty`;
             phetioClient.invoke( amplitudePropertyID, 'setValue', [ amplitude ] );
           }