What data analysis (research design) to use?

I'm about to throw my thesis out the window! I'm writing a thesis proposal, and I can't figure out what method I should use to analyze the data. Here's some important info:





Quasi-experiment (non-random sampling)


2 groups of about 25 students (one control and one treatment)


pretest and posttest





Am I leaving out any info that could help someone answer my question? Thanks!

What data analysis (research design) to use?
It is an analysis of covariance. It is like a one-way ANOVA of the effect of treatment (treatment vs. control) on posttest scores but you are adjusting the posttest scores for differences on the pretest. Pretest scores are the covariate.