You don’t have to spend tons of money for kids gear. I have been taking my kids ice fishing since they were about 3 years old. You can buy snow pants or bibs for around $20 or less. A coat about the same. Try Walmart, target ect. Most places are closing out winter gear now. Buy 2-3 pairs of gloves. Change their gloves when they get wet. Boots are being marked down now as well. Buy the boots a size or two big. Room to grow and room for socks. Costco sales a pack of Omni wool socks for a good price. If the boots are cheap buy two pairs. Change when wet. A heater is a must for kids. Keeps hands warm, I usually sit them in a chair and warm their feet a few times a day. I buy hand warmers and place them inside their gloves. Tell them to hold the hand warmer in their palm and make a fist around it to warm all their fingers. Buy toe warmers as well. They have an adhesive pad. Stick them on top of their sock, to help warm their toes. Most important bring plenty of snacks to eat, thermos of hot chocalate, have them pack some toys to play with. Fishing is only a small part of their experience. Playing around and having fun is generally what they do most of the time.