Here are some samples of ways students can demonstrate understanding:
One of the websites I love is ABCya.com. There are activities for all grade levels Pre-K -5 that are skills based and engaging. One activity I really enjoy with students is Story Maker. Here, students can type a story (or sentence) and illustrate it. This is a great way for students to show knowledge of spacing, letter/sound correspondence, beginning/middle/end, while getting to use some tech tools like the painting tools, formatting options, even inserting an image.
Using Excel spreadsheets is a tool 2nd and 3rd graders need to master. Collecting data, analyzing it, and showing it in a spreadsheet (you can even have students create graphs!) is a fun way for students to take data analysis to the next level and make it meaningful.