You can increase the price of many products at once using the bulk price increase feature.
First, select Shop Products from the lefthand panel.
Select the tickbox in the top left column or click All Products to select all products. You can also choose tests individually by clicking the checkboxes next to each product. Click Bulk Price.
Enter the dollar amount or percentage you'd like to increase the price by in the Increase Price field, then click OK.
Note: At this time, you can only perform bulk price increases, not bulk price decreases.