Don't be bashful! If you want comments, give comments. You don't need to be an expert photographer to express your opinion about the work of others. You don't need to go into great depth. A simple remark about cropping, composition, color, subject matter, etc. can be of just as much help to a budding photographer as an in-depth critique.
For this assignment, try your newfound talent out on creating a high-impact, colorful photo using Skittles, M&Ms, or a similar multi-colored candy. Be bold and try to find a way to make the photo different, standing out from anything you have seen before.