like this: http://docs.handsontable.com/0.18.0/demo-grouping-and-ungrouping.html
Hello Otto,
Hiding/unhiding columns and rows in the Spreadsheet is an available feature in the widget (https://demos.telerik.com/kendo-ui/spreadsheet/index). Let us know if you have another scenario in mind.
Regards,
Veselin Tsvetanov
Progress Telerik