There is no “fastest way” for children to eat calcium, common ways of calcium supplementation include: drinking milk, tofu, cheese and other calcium-containing foods to help replenish calcium; oral calcium carbonate, calcium gluconate, vitamin D3 and other medications, such as the need to use medications, need to be used under the guidance of a doctor. 1. If the child is only lacking calcium but not in discomfort, it is recommended to drink more milk and eat more calcium-containing foods such as tofu, green leafy vegetables and cheese to supplement. Daily sun exposure, vitamin D3 supplementation, and increased physical activity to promote calcium metabolism. 2. Children with calcium deficiency can take calcium carbonate, calcium gluconate and vitamin D3 orally to help quickly replenish calcium and relieve symptoms of severe calcium deficiency such as muscle spasms, perioral numbness, bone pain, and twitching of the hands and feet. If medication is needed, it should be used under a doctor’s supervision.