I have included sorting colors, shapes, and animals for AB, AAB, ABB, and ABC patterns. Students must extend either 3 or 4 spaces to finish the patterns. There are pages for students to sort all of one type of pattern on the same page, and pages where different types of patterns are included on the same page.
I print the extra pieces and have a bag of pieces for each card. Students have to decide which piece goes with each pattern. You could also organize the patterns into books, and have strips of Velcro on the opposite page with the options for extending the patterns.
These are great activities to put into an independent workbox system, during inclusion for your students to work on modified by similar work, or in your classroom in a small group or one-on-one setting.