Do some of your students have trouble with b and d reversals? Or do they always use capital B and D just to make sure they use the right letter?
I use the following visual reminder to help those students remember which way the lower case letter b and d are supposed to go. I had the reminders printed up in colour, on card, and then I attach the cards to desks using MacTac.
'b' and 'd' Reversal Desk Reminder by Clare Haagensen is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.