It is called Pongal in Tamilnadu. It's a five day celebration, where sugarcane, paddy field Pooja, worshipping Lord Surya plays a major part. Chakarai pongal, ven pongal are made at home and offered to Lord. The evenings are filled with folk dances, music and short dramas. When school reopens after Christmas holidays all of us would look forward to Pongal holidays for all five days it would be celebrations and celebrations only.
In West Bengal, we call it Makar Sankranti / Poush Parban and celebrate by making home made sweet delicacies like pithe (sweet rolls with coconut fillings), payesh (kheer), etc.