  We present a $L$-band (2.98--3.96$\mu$m) spectroscopic study of 8 young L
dwarfs with spectral types ranging from L2 to L7. Our spectra
(${\lambda}/{\Delta \lambda}\approx$ 250 to 600) were collected using the
Gemini Near-InfraRed Spectrograph. We first examine the young $L$-band spectral
sequence, most notably analyzing the evolution of the $Q$-branch of methane
absorption feature at 3.3 $\mu$m. We find the $Q$-branch feature first appears
between L3 and L6, as previously seen in older field dwarfs. Secondly, we
analyze how well various atmospheric models reproduce the $L$-band and
published near-IR (0.7--2.5 $\mu$m) spectra of our objects by fitting five
different grids of model spectra to the data. Best-fit parameters for the
combined near-IR and $L$-band data are compared to best-fit parameters for just
the near-IR data, isolating the impact that the addition of the $L$-band has on
the results. This addition notably causes a $\sim$100 K drop in the best-fit
effective temperature. Also, when clouds and a vertical mixing rate
($K_{\mathrm{zz}}$) are included in the models, thick clouds and higher
$K_{\mathrm{zz}}$ values are preferred. Five of our objects also have
previously published effective temperatures and surface gravities derived using
evolutionary models, age estimates, and bolometric luminosities. Comparing
model spectra matching these parameters to our spectra, we find disequilibrium
chemistry and clouds are needed to match these published effective
temperatures. Three of these objects are members of AB Dor, allowing us to show
the temperature dependence of the $Q$-branch of methane.
