My Take
Number Frames is a great basic app for instructional use. It is not meant as stand-alone practice for students, but as a way to make representations of mathematical concepts. Number frames are one of the standard tools used by teachers of elementary learners. Having a digital version available for student use for guided instruction, practice, and/or for mirroring on-screen for whole group instruction is a bonus for any classroom.
How I Use It
Number Frames by Math Learning Center helps students structure numbers into groups of five, ten, twenty, and one hundred. Students use the frame to represent, count, compose, and decompose numbers in a set range. For early learners, this helps them move away from one-by-one counting. The frames also helps them visual fact families and the commutative property. As students advance, frames can be constructed to help students visualize factors, products, and fractional parts. This tool required some instruction on use with my second grade students, but once they caught on it became easy for them to use. It is my recommendation to use this in conjunction with, not instead of, actual manipulative items on ten frames.