D's and B's and d's and b's
Even children taught with phonics can confuse d's and b's, especially when using the lowercase letters. However, this problem is especially prevalent with students who have been trained with whole word methods or in a phonics program with too many sight words.
The following exercises were developed to help students overcome this confusion. You need to overteach D, then overteach B in all-upper-case. Make sure you spend several short sessions over several days on each letter before moving on to the next letter. Each lesson consists of words to read and words to write. For example, for lesson 1, have the student read the words in the first 3 lines, number 1 - number 3. Have the student read across the page, not down the page. Then, go to number 4 on the third page. Have the student write each of these 4 words in all-upper-case as you read the word to them. After completing all four lessons in all-upper-case, you overteach d, then overteach b in all-lower-case.
Especially If your student has dyslexia, you should focus on only the approximate letter sound, and not the name, of each letter during all of these exercises. In this case, have your student only say the sound and not the name of the letter when doing the writing exercises and always refer to the letter by its approximate sound and never its name. After you have completed these exercises and have the sounds of each letter firmly ingrained in your student's brain, you can go over the writing exercises again and work on ingraining the name of each letter. Again, start with uppercase first and then move on to lowercase. Slow and steady wins the race!
If your student is still having trouble after these exercises, here's a technique Don Potter has found helpful with his remedial students:
I use a neat trick for helping students that confuse the b and d. I tell them to look at their mouth when they say the b. They will note that the lips form a horizonal line, the b also starts with a line. Then I have them say the /d/ they immediately note that it starts with a circle and the lips form a little circle. When we come to a "b" in reading, I ask them to think about whether they are going to make a line with their lips or not. I got this tip from Myrna McCulloch of the Riggs Institute. It works like charm for my students. Being multi-sensory it seems to work better than any of the other methods I have tried.
Here is the pdf file with the D's and B's and d's and b's: