About this app
Practice basic addition and subtraction concepts. Discs are counted, then covered, and some slide out from under the cover. Your job is to tell how many are still hidden under the cover. Work with numbers 1-5 or 1-10. Discs are displayed in a 5-frame or 10-frame format. The iPad version includes an option to use numbers to 20 in two 10 frames. This option was added at the request of elementary education teacher candidates at Augustana College in Rock Island, IL who were working with kindergarten students. The iPad version also includes an option to count or subtilize the number of discs. That option was added in response to a user request. Developed as part of the NumberSense Project at Augustana College in Rock Island, IL.
Latest release
What’s New
• Updated to support iOS12 - thank you for your patience. • A few other minor tweaks • As time allows, I'd enjoy hearing how you're using this app in the classroom and at home.
Audience growth
Ratings growth
Baseline captured. Growth appears after the crawler observes a changed rating count.
Momentum comes from crawler snapshots for the tracked storefront. “Viral growth signal” means unusually fast recent rating gains; it is an indicator, not download data.
Price tracking
Price intelligence
First snapshot captured. The trend line starts after the next crawler price observation.
- First observed Aug 12, 2026 · 4:54 PM Free
Screenshots
