My son is using the Earlybird Kindergarden Mathematics, published by Marshall Cavendish Education.  He has finished the first book K1A already. It contains sorting and matching activities and counting numbers from 1-10. My son found it easy to do the activities. The book contains many hands-on activities to make learning fun and interesting. It is filled with colorful illustrations to engage the student to an interesting math workbook! Though I find the book a bit too pricey 🙂

Note: I am not connected to Marshall Cavendish Education in any way and this review is based from my personal opinion.