By the age of four, many children have learned to pronounce the hard "C" and "K" sounds. But some children have difficulty with the pronunciation of these letters, as they are formed using the back portion of the tongue, rather than the front. In that case, the "K" or hard "C" sound in a word like "cat" is pronounced as a "T" sound, resulting the mispronunciation "tat." Make a game out of learning the tricks and don't be afraid to get silly to take the pressure off. Every child is different, so start with the method that seems most appealing to you and move on to another if the first method doesn't work.
Teach your child to say the hard "C" or "K" sounds while lying on his back on the floor. Gravity will naturally pull his tongue into the back of his mouth for a more correct position.
Get your child to cough to make the beginning sound of a "K" word. The act of coughing will keep the tongue down while also mimicking the "K" or hard "C" pronunciation.
Have your child hold down the front tip of his tongue with his finger while he attempts to pronounce the "K" words. This will keep him from being able to form the "T" sounds and help hold his tongue in the correct position.
Place a small food item, such as a piece of cereal, behind your child's bottom teeth, and tell him to hold it in place with his tongue while he pronounces the words. Once he gets the feel of keeping his tongue in the correct position to make a "K" sound, he will likely remember it and the cereal will no longer be necessary.
Add an "L" after the "K" sound in the word. Have your child say "Clat" rather than "Cat." With the extra letter, it may be easier for him to make the "K" sound. Once he gets the hang of it, have him try it dropping the "L."
Show your child what the tongue should look like when producing the "K" sound. Open your mouth and push the back of your tongue toward the roof of your mouth while keeping the front of your tongue down behind your bottom teeth. Have him mimic this.
Hold the tip of your child's tongue down with a sucker, and push the back of the tongue gently toward the back of the throat. Have him attempt to pronounce some "K" and hard "C" words while the sucker is in place. Do not try to force the tongue if your child seems like he is going to gag. Some children have a sensitive gag reflex and another less invasive method will be necessary. As an added incentive, when he correctly pronounces a "K" word he can eat the sucker.
Give your child drinks with straws rather than sippy cups to help develop the muscle that is used in producing the hard consonants. Thicker liquids that require harder sucking are especially beneficial.