Learn subtraction with eeBoo Subtraction Educational Flash Cards. An educational activity to introduce and reinforce knowledge of fundamental math skills. Helpful illustrations guide basic counting and borders are color-coded for easy sorting for ages 5 and up. Cards are easy to hold for small hands, double-sided, and durable. We are a women-owned business dedicated to sustainability, safety, and the creation of original and extraordinary gifts and toys. This item is made of 90% recycled materials, printed with vegetable-based inks. For over 25 years, eeBoo has created wholesome, educational games and activities that cultivate conversation, socialization, and skill-building while introducing our world.