  We present a collection of new, open-source computational tools for
numerically modeling recent large-scale observational data sets using modern
cosmology theory. Specifically, these tools will allow both students and
researchers to constrain the parameter values in competitive cosmological
models, thereby discovering both the accelerated expansion of the universe and
its composition (e.g., dark matter and dark energy). These programs have
several features to help the non-cosmologist build an understanding of
cosmological models and their relation to observational data: a built-in
collection of several real observational data sets; sliders to vary the values
of the parameters that define different cosmological models; real-time plotting
of simulated data; and $\chi^2$ calculations of the goodness of fit for each
choice of parameters (theory) and observational data (experiment). The current
list of built-in observations includes several recent supernovae Type Ia
surveys, baryon acoustic oscillations, the cosmic microwave background
radiation, gamma-ray bursts, and measurements of the Hubble parameter. In this
article, we discuss specific results for testing cosmological models using
these observational data. These programs can be found at
http://www.compadre.org/osp/items/detail.cfm?ID=12406.
