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] => Elementary Math
                            [slug] => elementary-math
                            [id] => 1743
                        )

                )

        )

    [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] => Biochemistry
                            [slug] => biochemistry
                            [id] => 1751
                        )

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

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

                    [4] => Array
                        (
                            [name] => Genetics
                            [slug] => genetics
                            [id] => 1753
                        )

                    [5] => Array
                        (
                            [name] => Microbiology
                            [slug] => microbiology
                            [id] => 1752
                        )

                )

        )

    [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] => ACT Science
                            [slug] => act-science
                            [id] => 1870
                        )

                    [1] => Array
                        (
                            [name] => MCAT
                            [slug] => mcat
                            [id] => 1865
                        )

                )

        )

)