EducationCity's Math module is a diverse collection of activities, interactive tools, tests, tutorials, games, and word problems. You can use the handy standards map to see how the different resources address various Common Core standards. All of the activities come with valuable support materials including teacher notes, lesson ideas, and worksheets. Grades 2 and 3 seem to include the largest number of activities.
Spend some time searching through all the offerings before introducing any one of them in a lesson. You can use the resources here individually, in small groups, or in whiteboard mode for whole-class instruction -- some will work better than others in certain scenarios. The interactive Topic Tools are probably best for whole-class instruction, and the Learn Screens (tutorials) are a great way to reinforce learning. The worksheets that accompany most activities could work well for independent classwork or as homework. The Thinkits take concepts a step further and promote critical thinking; it's probably best to use these as extension activities, once students have mastered a topic.
Continue reading