【Standardized Writing Methods】Our handwriting practice books use thick white cardboard, which is sturdy and reusable, with double-sided design and clear printing. The content has been repeatedly checked, making it a good helper for children's learning and practice. 2 pens and 20 refills are sufficient for repeated use, 2 silicone handwriting aid is provided to facilitate children to master the method of holding pen. 【Ink Magically Disappears】The matching refills of the hand writing practice book use magical ink, handwriting will automatically fade and disappear within 30 minutes after writing, so kids can used repeatedly. Through repeated practice, master English handwriting skills and write standard English words. It is an essential toddler writing practice set for children to learn calligraphy. Attention: Exposure to sunlight or windy areas can accelerate the disappearance of ink stains. 【Rich Learning Content】Magic grooved handwriting practice books contain 26 English Alphabet, drawing, 0-100 numbers and simple addition and subtraction, uses a combination of pictures and text, which will stimulate children's interest and attract their attention. Bright colors and cute shapes, which can improve children's cognition of letters, numbers, colors and shapes, exercise simple calculation skills and increase memory. 【Effective Way of Early Education】The handwriting book has three-dimensional groove design, follow the grooved paths, which is very helpful for improving their writing skills. Each copy page for preschool children contains attractive, effective, and practical exercises, allowing them to acquire valuable eye-hand coordination and handwriting skills. 【Designed for Early Education】Handwriting exercise books uses a combination of pictures and text, which will stimulate children's interest and attract their attention. The learn to write books is suitable for early education, which can not only help children improve their writing skills, but also guide children to master the correct posture of holding a pen.