Children heart rate monitoring plays an important role among human health research field. In this paper, a synchronized intelligent sensor network was designed for children heart rate monitoring. The ECG sensor, MMA7261QT accelerometer sensor and CSR BC4 Bluetooth module were accepted for heart rate monitoring. The experimental data features were extracted by the bistable stochastic resonance data processing method. The signal-to-noise ratio (SNR) maximum value was used to judge the children action state. The experimental results showed that the designed system provided an effective method for a big scale children health monitoring.