Summary

A simple game to learn or improve your understanding of the Roman numeral system.

Print Settings

Printer:

Sculpto+

Rafts:

Doesn't Matter

Supports:

No

Notes:

How many coins should I print?
As many as you want! I would suggest printing at least 3 of each value.

The coins are quite large, can I print them smaller?
Absolutely, the full size coins are probably best for the individual value and the sort the numbers excercises. I have printed coins in 60% size successfully (STLs for this are in the files section), they will likely print even smaller but I wouldn't recommend that.

What is the Roman Numeral System?

The numeric system represented by Roman numerals originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. Numbers in this system are represented by combinations of letters from the Latin alphabet. Roman numerals, as used today, are based on seven symbols: I=1, V=5, X=10, L=50, C=100, D=500, M=1000
https://en.wikipedia.org/wiki/Roman_numerals

The Roman numerals are added or subtracted based on their position in the written number. A smaller number before a larger number means the smaller number is subtracted from the larger. A larger number before a smaller number means the smaller number is added to the larger number.

It can sound quite complicated when explained, but 3 simple bulletpoints should be enough:

Small before large, subtract the small number from the larger number.
Large before small, add the two.
Never put more than one smaller number before a larger number.

Examples

I = 1
II = 2
III = 3 (NEVER IIV!)
IV = 4
VI = 6
CIV = 104
MMXVIII = 2018

Games and excercises

Individual values

If you've never worked with Roman numerals before, the first thing you should master is the individual values. Identifying the individual values is the basis for everything invovling Roman numerals.

Put the coins in a bag or put them, value side down, on a table. Draw a coin and identify the value. Keep going until you master the values.

Sort the numbers

A variation on the individual values excercise, take one coin of each value and sort the coins from small to large. You will need to identify the values before you can sort them correctly.

Growing number

The idea of this excercise is to improve your understanding of the structure of the Roman numeral system.

Put all the coins in a bag or on the table with the value facing down. Draw a coin and identify the value (as in the individual value excercise). Draw another coin and identify the combined value of the two. Keep going as long as you want or until you can no longer figure the number out. Use a tool like http://www.onlineconversion.com/roman_numerals_advanced.htm to validate your number.

Each coin drawn should be added to the end of the number, unless that would create an invalid number. If the coin cannot be added to the end of the number, add it to the start and continue. If the the coin cannot be added to either start or end of the number string, re-arrange your coins to make a valid number and continue. The goal is to become familiar with the structure of a valid Roman numeral.

As an example, consider these four draws:

I = 1
V, IV = 4
C, IVC is invalid, move the C to the front to get CIV = 104.
I, both CIVI and ICIV are invalid numbers and you cannot continue. Re-arrange your coins to make a valid a number. A valid number could be CVII = 107.

Got an idea for another excercise?

If you have ideas for other excercises, feel free to share them in the comments!

Roman Numeral Trainer