It's great to hear that you're enjoying our worksheets! Your printer should have an option to print in either black and white, or color. When you select "Print," one of the additional options on that screen should read "Properties." By clicking there, you should be given a set of additional features, including printing in black and white or gray scale, so that you don't use up all of your color ink.
If you're printing out in black and white, and the worksheets are still not printing to your satisfaction, please let us know by emailing our technical team at firstname.lastname@example.org. We'd love to work something out to make sure you get the best possible worksheets for your school!