South Dakota K-12 Email Security Intelligence:
DNS Authentication Profiling of 188 School District LEAs

Lokentra Research Team
Lokentra U.S. Email Security Index (ESI) — State Intelligence Series
April 22, 2026
research@monitorworkspace.com • monitorworkspace.com/scorecard

Abstract

We present DNS email security profiling for 188 K-12 LEAs in South Dakota, of which 159 have active domains (84.6% coverage). Domains were scored on the Lokentra 100-point Email Security Index (ESI) rubric (SPF 30 pts + DKIM 30 pts + DMARC 40 pts). South Dakota K-12 districts achieve an average ESI score of 6.4/100, with 1.9% earning Grade A or B (strong posture) and 92.5% receiving Grade F (minimal authentication). Only 6.9% have any DMARC record, and just 1.9% have DMARC at an enforcement level (quarantine or reject) — leaving 93.1% of districts fully vulnerable to email domain spoofing. This report provides entity-level data for all 159 scored domains including provider classification, authentication status, and ESI score, sourced from NCES CCD 2024-2025 and live DNS resolution conducted April 22, 2026.

Keywords: South Dakota, K-12 email security, DMARC, SPF, school district cybersecurity, DNS authentication, Google Workspace, education technology

1. Dataset Overview

Table 1. South Dakota K-12 Dataset Summary
MetricValue
Total K-12 LEAs in state188
Regular school districts171
Charter LEAs0
Other LEA types (state-operated, regional, etc.)17
LEAs with active internet domain159 (84.6%)
Domains DNS-profiled159
Data freshness (NCES CCD)2024-2025 school year
DNS scan dateApril 22, 2026

2. The Human Impact: Populations at Risk

To estimate human exposure, NCES national averages are applied to CCD 2024-2025 operational school counts: 381 students per school, 51 staff per school, and 2 parents or guardians per student. South Dakota K-12 districts collectively operate approximately 706 schools.

Table 2. Estimated Population Exposure from K-12 Email Security Gaps — South Dakota
PopulationTotal in DatasetAt Risk (No DMARC, 93.1%)Critically Exposed (Grade F, 92.5%)
Students268,986250,425248,812
Parents and guardians537,972500,851497,624
Staff and educators36,00633,52133,305
Total people842,964784,799779,741

Estimates based on NCES national averages. Individual district enrollment data can be linked via NCES LEAID for precise counts.

3. Authentication Findings

3.1 Protocol Adoption

Table 3. Email Authentication Protocol Adoption — South Dakota K-12
ProtocolSouth DakotaNational K-12 (ESI)vs. National
SPF (any configuration)17.0%79.7%-62.7pp
DKIM (key published)2.5%59.6%-57.1pp
DMARC (any policy)6.9%55.5%-48.6pp
DMARC at enforcement (quarantine/reject)1.9%~21.0%-19.1pp
DMARC at reject (full enforcement)0.0%~12.2%-12.2pp
No MX records (not receiving email)87.4%~10.0%+77.4pp

3.2 ESI Grade Distribution

Table 4. ESI Score Grade Distribution — South Dakota K-12
GradeScoreDistrictsShareInterpretation
A90–10010.6%Full enforcement
B70–8921.3%Strong posture
C50–6921.3%Partial protection
D30–4974.4%Weak configuration
F0–2914792.5%Minimal/no authentication
Average score6.4 / 100

3.3 Email Provider Distribution

Table 5. Email Provider Distribution — South Dakota K-12 (top providers)
ProviderDistrictsShare
Google Workspace53.1%
Microsoft 36542.5%
Barracuda10.6%
GoDaddy10.6%

4. District-Level Data

4.1 Top Performing Districts (Best ESI Scores)

Table 6. Top 15 South Dakota K-12 Districts by ESI Score
DistrictDomainCountyProviderSPFDKIMDMARC PolicyScoreGrade
East Dakota Educational Cooperative teachwell.org Minnehaha County Google Workspace quarantine 95 A
SD SCH FOR THE BLIND & VISUALLY IMPAIRED sdsbvi.northern.edu Brown County Microsoft 365 quarantine 85 B
Black Hills Special Services Cooperative bhssc.org Meade County Microsoft 365 none 70 B
Southeast Area Cooperative southeastareacoop.org Union County none 65 C
Sanborn Central School District 55-5 sanborncentral.com Sanborn County quarantine 60 C
Rapid City Area School District 51-4 rcas.org Pennington County none 40 D
Spearfish School District 40-2 spearfish.k12.sd.us Lawrence County Barracuda none 40 D
Bon Homme School District 04-2 bonhomme.k12.sd.us Bon Homme County none 35 D
Harrisburg School District 41-2 harrisburgdistrict41-2.org Lincoln County none 35 D
Brandon Valley School District 49-2 brandonvalleyschools.com Minnehaha County 30 D
Dakota Valley School District 61-8 dvschools.com Union County Microsoft 365 30 D
Oglala Lakota County 65-1 olcsd.com Oglala Lakota County Microsoft 365 30 D
Bowdle School District 22-1 bowdle.k12.sd.us Edmunds County 25 F
Brookings School District 05-1 brookings.k12.sd.us Brookings County 25 F
Chester Area School District 39-1 chester.k12.sd.us Lake County 25 F

4.2 Districts Most in Need of Improvement (Lowest ESI Scores)

Table 7. Bottom 15 South Dakota K-12 Districts by ESI Score
DistrictDomainCountyProviderSPFDKIMDMARC PolicyScoreGrade
Howard School District 48-3 howard.k12.sd.us Miner County 0 F
Alcester-Hudson School District 61-1 alcester-hudson.k12.sd.us Union County 0 F
Wilmot School District 54-7 wilmot.k12.sd.us Roberts County 0 F
North Central Special Ed Cooperative ncsec.k12.sd.us Brown County 0 F
Milbank School District 25-4 milbank.k12.sd.us Grant County 0 F
Deuel School District 19-4 deuel.k12.sd.us Deuel County Google Workspace 0 F
Britton-Hecla School District 45-4 britton.k12.sd.us Marshall County 0 F
Agar-Blunt-Onida School District 58-3 abo.k12.sd.us Sully County 0 F
Sisseton School District 54-2 sisseton.k12.sd.us Roberts County 0 F
Tea Area School District 41-5 teaschools.k12.sd.us Lincoln County 0 F
Hitchcock Tulare School District 56-6 hitchcock-tulare.k12.sd.us Spink County 0 F
McCook Central School District 43-7 mccookcentral.k12.sd.us McCook County 0 F
Selby Area School District 62-5 selby.k12.sd.us Walworth County 0 F
Groton Area School District 06-6 grotonarea.com Brown County GoDaddy 0 F
Aberdeen School District 06-1 aberdeen.k12.sd.us Brown County 0 F

4.3 County-Level Summary (Top 10 Counties by District Count)

Table 8. South Dakota County Distribution
CountyDistrictsWebsite Coverage
Minnehaha County9100.0%
Brown County6100.0%
Lake County650.0%
Oglala Lakota County616.7%
Roberts County580.0%
Union County5100.0%
Turner County5100.0%
Pennington County5100.0%
Codington County5100.0%
Charles Mix County580.0%

5. Policy Implications

These findings identify specific, actionable gaps in South Dakota's K-12 email security posture. The 93.1% DMARC gap represents districts that can be impersonated by any sender, enabling phishing campaigns targeting parents, students, and educators with no authentication failure. Key observations:

6. Data Availability

The full South Dakota K-12 dataset — 188 entities with NCES CCD enrichment (phone, address, grade span, school count, LEAID) and DNS authentication profiles — is available as part of the Lokentra ESI State Pack.

Table 9. Licensing Tiers
TierScopeSuggested Use
State Pack: South DakotaAll 188 K-12 LEAs, full DNS profile + CCD enrichmentRegional studies, state policy, outreach
K-12 NationalAll 50 states, 20,021+ K-12 LEAsNational K-12 cybersecurity research
Full Registry801,359+ entities across all sectorsComprehensive multi-sector research
API + UpdatesQuarterly re-scan, REST APILongitudinal studies, live dashboards

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Citation: Lokentra Research Team (2026). South Dakota K-12 Email Security Intelligence: DNS Authentication Profiling of 188 School District LEAs. Lokentra U.S. Email Security Index (ESI) — State Intelligence Series. https://lokentra-site.web.app/research/states/sd-k12-paper.html

Data sources: NCES Common Core of Data (CCD) 2024-2025; DNS records resolved via Google Public DNS (8.8.8.8) and Cloudflare (1.1.1.1). All entity data derived from publicly accessible government registries.

National baseline figures from Lokentra U.S. Education Sector Email Security Intelligence Dataset (March 2026). See education-dataset-paper.html for full methodology.