One activity you might want to consider is to make a rice frame for this template.  You can use plain white rice or you can use food colored ones:

• Print the template and color in the R r.  Point out to the child which is the capital R and which is the lowercase.
   
• OPTIONAL:  To food color rice, add a healthy amount of food coloring to two 1 tsp of rubbing alcohol in a ziploc bag.  
  • Pour in about 3/4 cup of UNCOOKED rice.     
  • Close the bag
  • Shake well (like shake and bake)
  • Pour onto a piece of wax paper or tinfoil to dry (put it in a cookie sheet so it doesn't accidentally get knocked on the floor)
  • Making the colored rice is messy and food color doesn't come out of clothes well... the shaking part can be done by kids, but the rest should be done by an adult.
  • I like using food coloring PASTE instead of drops as I find the color is richer, but drops work too. 
  • Let dry (about 1/2 a day -- less if you spread them out well in a warm airy place) -- once again, I never listen to my own advice... our rice had about 5 minutes to dry before we used it... we just made sure to have a damp rag to wash off our hands.
      
• On a separate piece of paper, let the kids spread a thick layer of glue all around the edge in a 1 to 2 inch border using popsicle sticks, old toothbrushes or old paintbrushes to spread the glue.  OR have them spread the glue in the center of the letters.
  • Red construction paper is great here (Red starts with R)  It also looks wonderful with white rice if you don't want the hassle of dying it...
  • OR die the rice red (it will likely look a bit pink) and glue on white paper. 
    OR die the rice a number of different colors and once they're dry mix them together to make a Rainbow frame.
        
• Pour on the rice
  • Let the kids press the rice into the glue with their fingers (it's nice to let them deal with TEXTURE during craft projects).  
  • I often ask the girls to describe/compare different textures as we craft (printer paper is softer than construction paper, glue is sticky, rice is bumpy and cold, etc)
      
• Point out that Rr is for Rice and Rr is for Red (if you used red construction paper, red rice or if you had them color the Rr's in red).  
    
• Remember to color in your letters.  Throughout the alphabet lessons, use a variety of mediums for coloring the letters (crayons, pencil crayons, markers, pens, pastels water color paints, tempra paints, finger paints, etc) 
    
• Whenever I do these projects with Kaitlyn, I get to draw pictures of words that start with the letter and then she gets to color them.  Don't stress about your drawing skills... the kids will love watching you draw!  Letter R words I drew were a picture of a rainbow, rainbow fish, two red roses, a ring, a road, a rotten red radish (I just drew smelly squiggles coming out of the radish to show it was rotten), a rake, a rope, a red raspberry, a raccoon and a rabbit.