Challenges: A calendar has a very limited number of uses, only allowing for teaching a singular conceptof time. It does not measure anything smaller than days, and therefore has limited learningopportunities.Weblink:-Interface.htmlCurrencyUse: Virtual currency can be used to teach place value.Benefits: Virtual currency has many different uses and can be used to teach many different mathconcepts, such as place value, values of different currencies and fractions.Challenges: There are a large variety of components with currency and may prove to be confusing tosome students initially.Weblink:-Interface.htmlNumber LineUse: The virtual number line can be used to teach adding and subtracting of whole numbers.