Have your child pick flowers like those mentioned above. Open a heavy book and line a page with wax paper. Your child can lay flowers on paper and press flower middles gently to flatten them.
Place a second wax paper sheet gently on top of flowers. Close the book and pile on more heavy books. Leave the pile for several days to press flowers.
Fold marbled or scrapbook paper in half so that the pattern is on the outside outside and blank side is inside. Cut to card size.
After several days, open the book. Gently peel the dried flowers off of the wax paper.

There are various methods to making a pressed flower card. To make yours, you can choose from the recommended options below:

Have your child lay the flowers on the card, and use clear stickers to hold the flowers in place. Peel the backings off of the clear stickers and place the stickers on top of flowers.
Have your child dip a toothpick in glue and glue the flowers down to the inside of the card. After it dies, he can poke a hole in front of card, then insert a pair of scissors into the hole and cut a “window” to display the flowers in. Cut wax paper slightly larger than the window. Use tape inside the edges that hang behind the paper to secure the window in place, so the tape will be hidden. You’ll see flowers through the card front’s wax paper window.
Your child can arrange flowers inside of a clear plastic sleeve, found at office supply stores. Cut a “window” in card’s front as above and tape the sleeve behind the card’s front window.
Let your child write a message to mom inside the card (under flowers if necessary). Happy Mother’s Day!

Pressed Flower Cards