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Cardstock isn’t just for making cards and postcards. You can use cardstock for many kids projects as well. Here are seven of those great activities.
Artwork Holders:  Take two sheets of cardstock and tape all ends together except for the top.  Decorate with stickers.  To make it more creative, cut the cardstock into fun shapes and use different colored cardstock. Now you can hold all your little ones artwork.  They will enjoy putting their work into something they created.
Flash Cards:  Fold cardstock in half both ways. Unfold and cut the 4 equal lines so you have four flashcards per page.  For younger kids, you can make numbers, letters, shapes, colors and animals on the flashcards.  If you aren’t very artistic, you can use stickers for animal flashcards.  For older kids, use mathematical problems, words with definitions and facts about history on the flashcards.  
Pretend Money:  All kids love pretend play.  Cardstock money will take them longer to rip than paper money.  Cut strips of the cardstock and have kids color it green.  After they are done, add denominations for them for hours of fun pretend play.  To get more creative, also make pretend credit cards and drivers licenses.  
Memory Game: Holding cardstock in a portrait presentation and fold in half the long way. Fold both sides to the center. Unfold and cut along lines to make 8 memory cards per page. If you are artistic draw animals and characters for a fun matching game.  If you aren’t very artistic, use stickers or go online and search for images that you can glue onto cards for animals and favorite characters.
Make a Book:  Give your child 3-4 pages of plain computer paper to color on. Encourage them to color on both sides.  When they are done take all pages and place them on top of the cardstock page.  Staple all pages down the middle. Don’t forget to give your book a name and even let them color the cover page.  
Make a Calendar: Make a calendar and let your child decorate with crayons and stickers.  Use calendars for chores, good behavior or for child’s activities.  Calendars are also good for teaching kids numbers and days of the week.  
Make Bookmarks:  Holding cardstock landscape, cut 4 equal strips.  Let your child decorate with markers, crayons and stickers.  Punch a whole in the top and tie a piece of ribbon or yarn through the hole.  These are great gifts for your kids to give or they can use them in their own books.