Baptists do not celebrate lent because it is not Biblical. You will not find any mention of Jews or Christians observing an annual period of 40 days of fasting and abstinence preceding the festival of the Passover, yet most of the “Christian” world observes a 40 day period called Lent, which precedes Easter Sunday. 
Some say that Baptists should participate in Lent for a number of reasons. I will give you three of the reasons that they cite, and give you the reasons that they are incorrect