You may be scheduling an event that should continue over multiple days or weeks, but only occur on weekdays. It's not possible to schedule an event that skips weekends but there are two ways to achieve the same result.
The calendar administrator can hide weekends. Then you can schedule an event over the dates (e.g. May 21 to June 7th) and see it displayed over just the weekdays within that date range.
To hide weekends:
Instead of creating one event that lasts over the whole date range, create a recurring event that repeats the needed number of times on weekdays only.
Here's how that would look in the event editor:
This would result in an event that repeats every weekday, skipping the weekends, until the specified end date.
To create a repeating event on weekdays only:
On the Teamup app, you can set up the same repeating sequence: Just choose Repeats Weekly, then select the weekdays and set the ending date.
See also: How to make weekend exceptions for recurring events