  We use in-plane tunneling spectroscopy to study the temperature dependence of
the local superconducting gap $\Delta(T)$ in electron-doped copper oxides with
various $T_c$'s and Ce-doping concentrations. We show that the temperature
dependence of $\Delta(T)$ follows the expectation of the
Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity, where
$\Delta(0)/k_{B}T_{c}\approx1.72\pm 0.15$ and $\Delta(0)$ is the average
superconducting gap across the Fermi surface, for all the doping levels
investigated. These results suggest that the electron-doped superconducting
copper oxides are weak coupling BCS superconductors.
