diff --git a/recursion_dynamic/coin_change_min/__init__.py b/recursion_dynamic/coin_change_min/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/recursion_dynamic/coin_change_min/coin_change_min_challenge.ipynb b/recursion_dynamic/coin_change_min/coin_change_min_challenge.ipynb
new file mode 100644
index 0000000..5acd777
--- /dev/null
+++ b/recursion_dynamic/coin_change_min/coin_change_min_challenge.ipynb
@@ -0,0 +1,169 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "This notebook was prepared by [Donne Martin](https://github.com/donnemartin). Source and license info is on [GitHub](https://github.com/donnemartin/interactive-coding-challenges)."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Challenge Notebook"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Problem: Determine the minimum number of ways to make n cents, given coins of denominations less than n cents.\n",
+    "\n",
+    "* [Constraints](#Constraints)\n",
+    "* [Test Cases](#Test-Cases)\n",
+    "* [Algorithm](#Algorithm)\n",
+    "* [Code](#Code)\n",
+    "* [Unit Test](#Unit-Test)\n",
+    "* [Solution Notebook](#Solution-Notebook)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Constraints\n",
+    "\n",
+    "* Do the coins have to reach exactly n cents?\n",
+    "    * Yes\n",
+    "* Can we assume we have an infinite number of coins to make n cents?\n",
+    "    * Yes\n",
+    "* Do we need to report the combination(s) of coins that represent the minimum?\n",
+    "    * No\n",
+    "* Can we assume the coin denominations are given in sorted order?\n",
+    "    * No\n",
+    "* Can we assume this fits memory?\n",
+    "    * Yes"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Test Cases\n",
+    "\n",
+    "* coins: None or n: None -> Exception\n",
+    "* coins: [] or n: 0 -> 0\n",
+    "* coins: [1, 2, 3] or [3, 2, 1] -> 2"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Algorithm\n",
+    "\n",
+    "Refer to the [Solution Notebook](http://nbviewer.ipython.org/github/donnemartin/interactive-coding-challenges/blob/master/recursion_dynamic/coin_change_min/coin_change_min_solution.ipynb).  If you are stuck and need a hint, the solution notebook's algorithm discussion might be a good place to start."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Code"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "class CoinChanger(object):\n",
+    "\n",
+    "    def make_change(self, coins, total):\n",
+    "        # TODO: Implement me\n",
+    "        pass"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Unit Test"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "**The following unit test is expected to fail until you solve the challenge.**"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# %load test_coin_change_min.py\n",
+    "from nose.tools import assert_equal, assert_raises\n",
+    "\n",
+    "\n",
+    "class TestCoinChange(object):\n",
+    "\n",
+    "    def test_coin_change(self):\n",
+    "        coin_changer = CoinChanger()\n",
+    "        assert_raises(TypeError, coin_changer.make_change, None, None)\n",
+    "        assert_equal(coin_changer.make_change([], 0), 0)\n",
+    "        assert_equal(coin_changer.make_change([1, 2, 3], 5), 2)\n",
+    "        assert_equal(coin_changer.make_change([3, 2, 1], 5), 2)\n",
+    "        assert_equal(coin_changer.make_change([3, 2, 1], 8), 3)\n",
+    "        print('Success: test_coin_change')\n",
+    "\n",
+    "\n",
+    "def main():\n",
+    "    test = TestCoinChange()\n",
+    "    test.test_coin_change()\n",
+    "\n",
+    "\n",
+    "if __name__ == '__main__':\n",
+    "    main()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Solution Notebook\n",
+    "\n",
+    "Review the [Solution Notebook](http://nbviewer.ipython.org/github/donnemartin/interactive-coding-challenges/blob/master/recursion_dynamic/coin_change_min/coin_change_min_solution.ipynb) for a discussion on algorithms and code solutions."
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.5.0"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/recursion_dynamic/coin_change_min/coin_change_min_solution.ipynb b/recursion_dynamic/coin_change_min/coin_change_min_solution.ipynb
new file mode 100644
index 0000000..d1960fb
--- /dev/null
+++ b/recursion_dynamic/coin_change_min/coin_change_min_solution.ipynb
@@ -0,0 +1,242 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "This notebook was prepared by [Donne Martin](https://github.com/donnemartin). Source and license info is on [GitHub](https://github.com/donnemartin/interactive-coding-challenges)."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Solution Notebook"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Problem: Determine the minimum number of ways to make n cents, given coins of denominations less than n cents.\n",
+    "\n",
+    "* [Constraints](#Constraints)\n",
+    "* [Test Cases](#Test-Cases)\n",
+    "* [Algorithm](#Algorithm)\n",
+    "* [Code](#Code)\n",
+    "* [Unit Test](#Unit-Test)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Constraints\n",
+    "\n",
+    "* Do the coins have to reach exactly n cents?\n",
+    "    * Yes\n",
+    "* Can we assume we have an infinite number of coins to make n cents?\n",
+    "    * Yes\n",
+    "* Do we need to report the combination(s) of coins that represent the minimum?\n",
+    "    * No\n",
+    "* Can we assume the coin denominations are given in sorted order?\n",
+    "    * No\n",
+    "* Can we assume this fits memory?\n",
+    "    * Yes"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Test Cases\n",
+    "\n",
+    "* coins: None or n: None -> Exception\n",
+    "* coins: [] or n: 0 -> 0\n",
+    "* coins: [1, 2, 3] or [3, 2, 1], n: 5 -> 2"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Algorithm\n",
+    "\n",
+    "We'll use top down dynamic programming with memoization.\n",
+    "\n",
+    "* Base case: If the total is 0, return 0\n",
+    "* If the total is already in the memo, return it\n",
+    "* For each coin denomination:\n",
+    "    * If this coin > total, continue\n",
+    "    * Recurse, decreasing total by the coin denomination, keeping track of the min return\n",
+    "* Set memo[total] to the min value + 1\n",
+    "* Return the memo[total]\n",
+    "\n",
+    "<pre>\n",
+    "total: 5\n",
+    "coins: [1,2,3]\n",
+    "memo key: total value: min ways\n",
+    "memo = {\n",
+    "    1: 1,\n",
+    "    2: 1,\n",
+    "    3: 1,\n",
+    "    4: 2,\n",
+    "    5: 2\n",
+    "}\n",
+    "                              5\n",
+    "                           1, 2, 3\n",
+    "                          /\n",
+    "                         4\n",
+    "                      1, 2, 3\n",
+    "                     /\n",
+    "                    3\n",
+    "              1,    2,    3\n",
+    "             /       \\     \\____\n",
+    "            2         1         0\n",
+    "         1, 2, 3   1, 2, 3\n",
+    "        /   |\n",
+    "       1    0\n",
+    "    1, 2, 3\n",
+    "   /\n",
+    "  0\n",
+    "</pre>\n",
+    "\n",
+    "Complexity:\n",
+    "* Time: O(t * n), where t is the total and n is the number of coin denominations\n",
+    "* Space: O(t) for the recursion depth"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Code"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import sys\n",
+    "\n",
+    "\n",
+    "class CoinChanger(object):\n",
+    "\n",
+    "    def make_change(self, coins, total):\n",
+    "        if coins is None or total is None:\n",
+    "            raise TypeError('coins or total cannot be None')\n",
+    "        if not coins or total == 0:\n",
+    "            return 0\n",
+    "        cache = {}\n",
+    "        return self._make_change(coins, total, cache)\n",
+    "\n",
+    "    def _make_change(self, coins, total, cache):\n",
+    "        if total == 0:\n",
+    "            return 0\n",
+    "        if total in cache:\n",
+    "            return cache[total]\n",
+    "        min_ways = sys.maxsize\n",
+    "        for coin in coins:\n",
+    "            if total - coin < 0:\n",
+    "                continue\n",
+    "            ways = self._make_change(coins, total - coin, cache)\n",
+    "            if ways < min_ways:\n",
+    "                min_ways = ways\n",
+    "        cache[total] = min_ways + 1\n",
+    "        return cache[total]"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Unit Test"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Overwriting test_coin_change_min.py\n"
+     ]
+    }
+   ],
+   "source": [
+    "%%writefile test_coin_change_min.py\n",
+    "from nose.tools import assert_equal, assert_raises\n",
+    "\n",
+    "\n",
+    "class TestCoinChange(object):\n",
+    "\n",
+    "    def test_coin_change(self):\n",
+    "        coin_changer = CoinChanger()\n",
+    "        assert_raises(TypeError, coin_changer.make_change, None, None)\n",
+    "        assert_equal(coin_changer.make_change([], 0), 0)\n",
+    "        assert_equal(coin_changer.make_change([1, 2, 3], 5), 2)\n",
+    "        assert_equal(coin_changer.make_change([3, 2, 1], 5), 2)\n",
+    "        assert_equal(coin_changer.make_change([3, 2, 1], 8), 3)\n",
+    "        print('Success: test_coin_change')\n",
+    "\n",
+    "\n",
+    "def main():\n",
+    "    test = TestCoinChange()\n",
+    "    test.test_coin_change()\n",
+    "\n",
+    "\n",
+    "if __name__ == '__main__':\n",
+    "    main()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Success: test_coin_change\n"
+     ]
+    }
+   ],
+   "source": [
+    "%run -i test_coin_change_min.py"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.4.3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/recursion_dynamic/coin_change_min/test_coin_change_min.py b/recursion_dynamic/coin_change_min/test_coin_change_min.py
new file mode 100644
index 0000000..2440185
--- /dev/null
+++ b/recursion_dynamic/coin_change_min/test_coin_change_min.py
@@ -0,0 +1,22 @@
+from nose.tools import assert_equal, assert_raises
+
+
+class TestCoinChange(object):
+
+    def test_coin_change(self):
+        coin_changer = CoinChanger()
+        assert_raises(TypeError, coin_changer.make_change, None, None)
+        assert_equal(coin_changer.make_change([], 0), 0)
+        assert_equal(coin_changer.make_change([1, 2, 3], 5), 2)
+        assert_equal(coin_changer.make_change([3, 2, 1], 5), 2)
+        assert_equal(coin_changer.make_change([3, 2, 1], 8), 3)
+        print('Success: test_coin_change')
+
+
+def main():
+    test = TestCoinChange()
+    test.test_coin_change()
+
+
+if __name__ == '__main__':
+    main()
\ No newline at end of file