For convenience, we have organized some of the available activities by textbook. There are certain topics that have more than one activity available, so if you have particular interest in a certain topic, you may find more choices by using the Find materials by search. Some of the activities on our site may not completely correspond to a particular textbook. If you would like to modify these materials to fit your own textbook or curriculum better, you can do so as long as you follow the guidelines outlined and acknowledge the original author. For more about modifying activities, you can consult the FAQ part of the website. If you create materials based on ours and would be willing to share yours, please contact us.