Array
(
    [1723] => Array
        (
            [parent_category_id] => 1723
            [parent_category] => Array
                (
                    [id] => 1723
                    [slug] => math
                    [name] => Math
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => Algebra 1
                            [slug] => algebra-1
                            [id] => 1725
                        )

                    [1] => Array
                        (
                            [name] => Geometry
                            [slug] => geometry
                            [id] => 1727
                        )

                    [2] => Array
                        (
                            [name] => Prealgebra
                            [slug] => prealgebra
                            [id] => 1724
                        )

                )

        )

    [1744] => Array
        (
            [parent_category_id] => 1744
            [parent_category] => Array
                (
                    [id] => 1744
                    [slug] => science
                    [name] => Science
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => Anatomy
                            [slug] => anatomy
                            [id] => 1749
                        )

                    [1] => Array
                        (
                            [name] => Biology
                            [slug] => biology
                            [id] => 1746
                        )

                    [2] => Array
                        (
                            [name] => Botany
                            [slug] => botany
                            [id] => 1756
                        )

                    [3] => Array
                        (
                            [name] => Ecology
                            [slug] => ecology
                            [id] => 1755
                        )

                    [4] => Array
                        (
                            [name] => Physiology
                            [slug] => physiology
                            [id] => 1750
                        )

                    [5] => Array
                        (
                            [name] => Zoology
                            [slug] => zoology
                            [id] => 1757
                        )

                )

        )

    [1903] => Array
        (
            [parent_category_id] => 1903
            [parent_category] => Array
                (
                    [id] => 1903
                    [slug] => special-needs-learning
                    [name] => Special Needs and Learning Support
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => ADHD
                            [slug] => adhd
                            [id] => 1907
                        )

                    [1] => Array
                        (
                            [name] => Special Needs
                            [slug] => special-needs
                            [id] => 1906
                        )

                )

        )

    [1856] => Array
        (
            [parent_category_id] => 1856
            [parent_category] => Array
                (
                    [id] => 1856
                    [slug] => test-prep-exams
                    [name] => Test Prep and Exams
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => GED
                            [slug] => ged
                            [id] => 1866
                        )

                )

        )

)