Creativity is both a learning experience and a lot of fun.
If you are insistent on purchasing them, please refer to the FAQ . The POP Math Archive collects items about mathematics which may explain this wierd behavior. A center for teachers, students, researchers, parents, educators and citizens who have an interest in mathematics education. Mathematics Gems Frank Potter's Science Gems. Eisenhower National Clearinghouse for Mathematics and Science ENC provides K-12 teachers with a central source of information on mathematics and science curriculum materials.